There's no singular cause for these periodic releases and the delays that they suffered. Software development is a complex and surprisingly free hax pro poorly understood business; there's no one "right way" to develop and manage a project. That is, there's no reliable process or methodology that will ensure a competent team can actually produce working, correct software on time or on budget. A system that works well with one team or on one project can easily fail when used on a different team or project.
Nonetheless, computer scientists, software engineers, and developers have tried to formalize and describe different processes for building software. The process MS Office 2010 crack historically associated with Microsoft—and the process most known for these long development cycles and their delays—is known as the waterfall process.
The basic premise is that progress goes one way. The requirements for a piece of software are gathered, then the software is designed, then the design is implemented, then the implementation is tested and verified, and then, once it has shipped, it goes into maintenance mode.