How many Agile developers does it take to change a lightbulb? Four.
– one to tell you how much the old lightbulb wasted,
– one to document what you would look at, if it were light enough to see,
– one to determine whether it’s an enhancement or a bug fix, and
– one to break the news that you’ll have to sit in the dark until the following sprint.

How many marketers does it take to change a lightbulb? Three.
– one to write the business case that the ROI for the lightbulb change is $1.2 million a year,
– one to argue about project ownership — the switch is in IT but the fixture is in Marketing.
– one to complain after code complete that they assumed the new lightbulb would be halogen.

How many web analysts does it take to change a lightbulb? Three.
– one to A/B test whether productivity is higher with the new lightbulb,
– one to measure how many new people the light attracts to the area, and
– one to explain to the business why they can’t wait until two weeks after the lightbulb change to request reporting on the improvement in energy consumption.