The 100k Proposition

Liz KeoghApril 2011

Meet the Team

PM Analyst Tester

Developers

Assumed Costs per Day

£700

£350

The Team’s Budget

£800kover

1 year

The Team’s Scope

4 features every 2 weeks

(80 features)

Quality

75% of features are used

10% of timeis bugfixing

Quality

A bug takes ½ day on average

Each week, 4 devs fix 8 bugs

Over the project, devs fix 320 bugs

The Goal

To show how Agile trainingfor a new team

can pay for itselfby reducing the costof an £800k project

by £100k.Coach

Descoping a feature

Hmm! They won’t really need that.

Descoping a feature

Each feature takes 1 dev 10 daysand 1 tester 2 ½ days

Saving:12 ½ x £350 = £4375

Descoping a feature

If we get 50% of unused features out

Saving:12.5% of £800k = £100k

Done!

That was easy!

Can we do it without

descoping?

The Goal

To show how Agile trainingfor a new team

can pay for itselfby reducing the cost

of the projectwithout reducing

the scope.Coach

Finding a bug earlyOops! We

found a bug!

Oops! Let me fix that…

Finding a bug early

Now:

½ hour = £25

In 2 months:

½ day = £175

Saving: £150 per bug

Finding a bug early

If we do it for ½ the bugs,saving over the project

½ x £150 x 320 = £24,000

Increasing code quality by 25%

This is much

better!Do I get to do

something new then?

Increasing code quality by 25%

4 dev days per week -> 3½ tester day per week -> ¼(fewer bugs to write up too)

Saving: £436.50 per week

If this happens ½ way through the project:

Saving: £8730

Increasing code quality by 25%Hold on. We take ½ hour now, not ½

day!

For ½ the bugs…

Cheat. You can’t count it twice!

Increasing code quality by 25%

4 dev days per week -> 3 (x ½ the bugs)2 dev hours per week -> 1 ½ (x ½ the bugs)½ tester day per week -> ¼

Saving for ½ the project: £5,730

Co-location and collaboration

If you could do the same project again with the same people and the

same requirements and technologies, how long

would it take?

Co-location and collaboration

At least 60% of a project is learning.

Co-location and collaboration

Increasing the rate of learning by 10% (really 20% but not counting other things twice) = 60% x 10% x 800k

Saving: £48,000

Co-location and collaboration

Co-location isimpossible

here!

That’s a shame. Let’s look at some other practices…

Learning comes mostly from

Co-location 50% £24,000Stand-ups 17% £8,000Retrospectives 17% £8,000Breaking down stories 8% £4,000Showcases 8% £4,000

Saving without co-location: £24,000

Late Change in RequirementsTime taken to agree change and update documentationreduced from 1 day to 1 hour

10% of analysis needs changing

6 hours x £50 x 10% x 200 days

Saving: £6,000

Automated testsThe cost of testing goes

up linearly as the code grows.

Automated tests

Cost of developers helping with automated tests at 1 day every 2 weeks: £7000

Not needing to hire another tester in the last ¼ of the project: £17,500

Saving: £10,500

Motivation and effectiveness

I get to see my work working!

I get feedback on mine!

More time exploring, less time writing bug reports!

Motivation and Effectiveness

If motivation makes teamonly 4% more effective

Saving: £32,000

Practices Total earnedFinding bugs early £24,000Increasing code quality £5,730Learning practices £24,000Changes in requirements £6,000Automated testing £10,700Motivation & effectiveness

£32,000

Total £102,430

Done!Done!

The numbers provided here are fairly conservative, and these are just

some of the benefits Agile can offer.

The Real Benefit

The real benefit of Agile over Waterfall happens when we showcase or release, and find out we did the wrong thing.

Ideally, we’re only wrong by 2 weeks, instead of 1 year.

The Real BenefitOr, we get to release early, and start getting benefit from the right thing.

That means 6 months extra of earning money from the early release.

Either way, that’s a lot of cash.

Agile.Why wouldn’t you do it?