Lessons · Project management · crashing vs fast-tracking
Crashing and fast-tracking: two ways to buy time, at two different prices
Crashing adds resources to critical activities and costs money; fast-tracking overlaps activities that were planned in sequence and costs risk.
Hone is a place to practise a career, one idea a day. This is one of its lessons, written out in full and free to read without an account.
In beta. This lesson was written for Hone and has not yet been checked by an experienced project manager. Practice material, not professional advice. What that means.
What it is for
The sponsor needs the date back by two weeks. There are two honest answers: pay for it, or gamble for it. Knowing which one you are offering, and saying so, is the difference between a recovery and a second slip.
How to think about it
Only shorten critical activities: shortening anything else changes nothing. To crash, compute cost per week saved for each candidate and buy the cheapest week first. To fast-track, find sequential activities that could overlap and name the rework risk out loud.
Worked example
Testing: 8 weeks at $40,000, or 6 weeks at $52,000 with a second testerA crash option.
Crash cost = (52,000 − 40,000) / (8 − 6) = $6,000 per week savedEach week bought costs $6,000.
Overlap writing the manual with the last 2 weeks of the buildFast-tracking. Zero cost, but if the build changes, the manual is rewritten.
Stop crashing when the path is no longer criticalOnce another path is longest, more money on this one buys nothing.
Your turn
Write which method costs money rather than risk.
adds resources to critical activities and raises the cost.
Solve one, graded on the server
The trap
Crashing an activity that is not on the critical path. It gets done sooner, the project does not, and the money is gone.
Now you try
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