The triangle of project management is a well-known model, used through and through since ages. I assume most software developers, even junior ones, are familiar with those: TimeCostScope As for my personal experience in the software industry, all projects have been behind schedule, with only a few exceptions for small projects (some man-months). The reason might probably because initial estimations were too low, either by accident or on purpose, but that is a subject best tackled in anothe