Reasons for ėDeath Marchî projects
Politics, politics, politics
Naive promises made by marketing, senior executives, naive project managers, etc.
Naive optimism of youth: ėWe can do it over the weekend!î
The ėstart-upî mentality of fledgling, entrepreneurial companies.
The ėMarine Corpsî mentality: Real programmers donít need sleep!
Intense competition caused by ...
Unexpected and/or unplanned crises - e.g. your hardware/software vendor just went bankrupt, or your three best programmers died in the same car accident.