Model: Uncertainty of requirements defines whether to work waterfall, agile or beyond agile
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graveyard: agile does not work
"if a project was in the graveyard I walked away"
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simple
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managers teach the best practices
agile has no value here
Complicated problems
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experts are expensive
get a team to do what the experts tell
"harvest their knowledge, turn it into stories"
Complex problems
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there are no experts
"hire a bunch of bright people, turn them loose and say: figure it out"
try something, try something else
if something stops working, try something else