estimation or, "how to dig your grave"
DESCRIPTION
Clients need to know how much a project will cost. Waterfall development is always late and over-budget. Agile development is done when it's done. You're left with estimates that you know are too low and then you squeeze them anyway. It shouldn't be this way. We'll look at how this happens, early warning signs, ways out and ways of avoiding it in the first place.TRANSCRIPT
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Estimation
Or,“How to Dig your own Grave”
Rowan Merewood
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Who
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Who
● Software Engineer● & Team Lead● at Ibuildings
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Who
● Software Engineer● & Team Lead● at Ibuildings
● @rowan_m
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Why
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Why
● I've seen (& made) mistakes
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Why
● I've seen (& made) mistakes
● You can avoid them
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Why
● I've seen (& made) mistakes
● You can avoid them
● Make your own
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What could possibly go wrong?
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Sales create estimates
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Sales create estimates
● Use skills correctly
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Sales create estimates
● Use skills correctly● Send a dev with sales
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Sales create estimates
● Use skills correctly● Send a dev with sales
● If you're sales & dev...
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Sales create estimates
● Use skills correctly● Send a dev with sales
● If you're sales & dev...
remember which hat you're wearing
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Lone developer creates estimates
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Lone developer creates estimates
● It's ok, he's a ROCKSTAR
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Lone developer creates estimates
● It's ok, he's a ROCKSTAR
● Independent estimates
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Lone developer creates estimates
● It's ok, he's a ROCKSTAR
● Independent estimates
● Or, at least review
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Estimate from detailed task lists
![Page 20: Estimation or, "How to Dig your Grave"](https://reader034.vdocument.in/reader034/viewer/2022051400/5577df1ad8b42a7b7b8b4a54/html5/thumbnails/20.jpg)
Estimate from detailed task lists
● You know it will change
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Estimate from detailed task lists
● You know it will change
● Gives misplaced confidence
![Page 22: Estimation or, "How to Dig your Grave"](https://reader034.vdocument.in/reader034/viewer/2022051400/5577df1ad8b42a7b7b8b4a54/html5/thumbnails/22.jpg)
Estimate from detailed task lists
● You know it will change
● Gives misplaced confidence
● Encourages micro-management
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Estimate a day as 8 hours
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Estimate a day as 8 hours
● 16 hr. task == 2 days
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Estimate a day as 8 hours
● 16 hr. task == 2 days(ha ha – you're cute)
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Estimate a day as 8 hours
● 16 hr. task == 2 days(ha ha – you're cute)
● You are not a code machine
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Estimate a day as 8 hours
● 16 hr. task == 2 days(ha ha – you're cute)
● You are not a code machine
● Even if you are,your team is not
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Estimate a day as 8 hours
● 16 hr. task == 2 days(ha ha – you're cute)
● You are not a code machine
● Even if you are,your team is not
● Dev: 6 hr. Lead: 4 hr.
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Estimate in hours
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Estimate in hours
● Still too much detail
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Estimate in hours
● Still too much detail
● Use ¼ days
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Estimate in hours
● Still too much detail
● Use ¼ days● ¼, ½, 1, 2, 3 days
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Estimate in hours
● Still too much detail
● Use ¼ days● ¼, ½, 1, 2, 3 days
● 1, 3, 5, 7 days
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Estimate in hours
● Still too much detail
● Use ¼ days● ¼, ½, 1, 2, 3 days
● 1, 3, 5, 7 days● Larger increments,
larger projects
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Just estimate coding time
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Just estimate coding time
● Remember your overheads
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Just estimate coding time
● Remember your overheads
● Remember team overheads
![Page 38: Estimation or, "How to Dig your Grave"](https://reader034.vdocument.in/reader034/viewer/2022051400/5577df1ad8b42a7b7b8b4a54/html5/thumbnails/38.jpg)
Just estimate coding time
● Remember your overheads
● Remember team overheads
● Think about dependencies
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Estimates as commitments
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Estimates as commitments
● Well, yes and no...
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Estimates as commitments
● Well, yes and no...
● List and quantify risk
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Estimates as commitments
● Well, yes and no...
● List and quantify risk● Estimates != schedule
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Waterfall estimates are useless
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Waterfall estimates are useless
● Fine, stop calling yourself an engineer
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Waterfall estimates are useless
● Fine, stop calling yourself an engineer
● Lots of work in“off-the-shelf” tasks
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Waterfall estimates are useless
● Fine, stop calling yourself an engineer
● Lots of work in“off-the-shelf” tasks
● Cone of Uncertainty
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Agile means we can't estimate
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Agile means we can't estimate
“Yeah, well, you know, that's just like, your opinion, man.”
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Agile means we can't estimate
● Over-reaction to Waterfall
“Yeah, well, you know, that's just like, your opinion, man.”
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Agile means we can't estimate
● Over-reaction to Waterfall
● Excuse to drop software engineering and just hack it
“Yeah, well, you know, that's just like, your opinion, man.”
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Enough mistakes, time for a treat
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Help your client understand
● Estimates as a budget
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Help your client understand
● Estimates as a budget
● The Holy Triangle● MoSCoW● Kano model
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Holy Triangle
Good
Fast
Cheap
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Holy Triangle
Good
Fast
Cheap
Scope
Time
CostQuality
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MoSCoW
● Must● Should● Could● Won't
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MoSCoW
● Must● Should● Could● Won't
Density
Capacity
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MoSCoW
● Must● Should● Could● Won't
Density
![Page 59: Estimation or, "How to Dig your Grave"](https://reader034.vdocument.in/reader034/viewer/2022051400/5577df1ad8b42a7b7b8b4a54/html5/thumbnails/59.jpg)
MoSCoW
● Must● Should● Could● Won't
Density
![Page 60: Estimation or, "How to Dig your Grave"](https://reader034.vdocument.in/reader034/viewer/2022051400/5577df1ad8b42a7b7b8b4a54/html5/thumbnails/60.jpg)
MoSCoW
● Must● Should● Could● Won't
Density
![Page 61: Estimation or, "How to Dig your Grave"](https://reader034.vdocument.in/reader034/viewer/2022051400/5577df1ad8b42a7b7b8b4a54/html5/thumbnails/61.jpg)
MoSCoW
● Must● Should● Could● Won't
Density
![Page 62: Estimation or, "How to Dig your Grave"](https://reader034.vdocument.in/reader034/viewer/2022051400/5577df1ad8b42a7b7b8b4a54/html5/thumbnails/62.jpg)
MoSCoW
● Must● Should● Could● Won't
Density
![Page 63: Estimation or, "How to Dig your Grave"](https://reader034.vdocument.in/reader034/viewer/2022051400/5577df1ad8b42a7b7b8b4a54/html5/thumbnails/63.jpg)
Kano Model
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Kano Model
● Basic functionality● Performance● Exciters
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Kano Model
● Basic functionality● Performance● Exciters Exciters
Performance
Basic
High Satisfaction
Low Satisfaction
FeatureAbsent
FeaturePresent
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Earn their trust, then get agile
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Earn their trust, then get agile
● Low risk, fixed price to start
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Earn their trust, then get agile
● Low risk, fixed price to start
● Create a roadmap
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Earn their trust, then get agile
● Low risk, fixed price to start
● Create a roadmap
● Move to sprint-based work
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Gamble with Planning Poker
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Gamble with Planning Poker
● The whole team makes the commitment
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Gamble with Planning Poker
● The whole team makes the commitment
● Combines independent estimates and review
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And now mistakes during projects
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Lose track of time
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Lose track of time
● Developers hate time-tracking
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Lose track of time
● Developers hate time-tracking
● Automate if you can
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Lose track of time
● Developers hate time-tracking
● Automate if you can● Include it in
stand-ups to update the burn-down
![Page 78: Estimation or, "How to Dig your Grave"](https://reader034.vdocument.in/reader034/viewer/2022051400/5577df1ad8b42a7b7b8b4a54/html5/thumbnails/78.jpg)
Estimate bugs
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Estimate bugs
● “Nein, nein, nein! Das ist verboten!”-- @dzuelke
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Estimate bugs
● “Nein, nein, nein! Das ist verboten!”-- @dzuelke
● You do not know the size of the problem
![Page 81: Estimation or, "How to Dig your Grave"](https://reader034.vdocument.in/reader034/viewer/2022051400/5577df1ad8b42a7b7b8b4a54/html5/thumbnails/81.jpg)
Estimate bugs
● “Nein, nein, nein! Das ist verboten!”-- @dzuelke
● You do not know the size of the problem
● Spend 3 days investigating – change 1 line of code
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Try to catch up
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Try to catch up
● [wo]man up and admit you're wrong
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Try to catch up
● [wo]man up and admit you're wrong
● Don't burn yourself or your team out
![Page 85: Estimation or, "How to Dig your Grave"](https://reader034.vdocument.in/reader034/viewer/2022051400/5577df1ad8b42a7b7b8b4a54/html5/thumbnails/85.jpg)
Try to catch up
● [wo]man up and admit you're wrong
● Don't burn yourself or your team out
● Work overtime and you set a precedent
![Page 86: Estimation or, "How to Dig your Grave"](https://reader034.vdocument.in/reader034/viewer/2022051400/5577df1ad8b42a7b7b8b4a54/html5/thumbnails/86.jpg)
Skip the review
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Skip the review
● Make time to learn
![Page 88: Estimation or, "How to Dig your Grave"](https://reader034.vdocument.in/reader034/viewer/2022051400/5577df1ad8b42a7b7b8b4a54/html5/thumbnails/88.jpg)
Skip the review
● Make time to learn● Share your mistakes,
so others avoid them
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Credits
● All sculpture/photos© Tamra Kohlhttp://www.flickr.com/photos/claylindo/
(Used with kind permission)
● Thank you!
● Photo jiggery-pokery:http://pixlr.com/o-matic/
● Background:http://www.colourlovers.com/pattern/635/Death_Flowers