#6 - Windows Vista

Windows XP wasn’t supposed to last as long as it did. As soon as XP shipped in 2001, work got under way for the next version. The feature list got bigger and more ambitious, and it was shown off with great following at Microsoft’s Professional Developers Conference in 2003. Those plans were moved aside completely in August 2004 and in 2005 it was found to be crashing a lot. The design goals of what was eventually named Windows Vista were admirable. Unfortunately, the cumbersome and disorganized project took more than five years to deliver unsatisfactory results.

When it debuted in January 2007, Vista got mostly negative reviews. Nobody knows how much it really cost Microsoft, but it damaged the company's reputation.

#5 - Apple

In 1985, Apple’s founder Steve Jobs recruited former Pepsi-Cola executive John Sculley to act as Apple's CEO, in order to help grow the company. He did this because of his own erratic and temperament behavior which was putting a strain on his relationship with his team members as well the Board of Directors of the company.

Facing a sales slump due to competition from companies like IBM and Compaq, Jobs' relationship with Sculley deteriorated which resulted in his expulsion from the company he and Steve Wozniak founded.

The 11-year period that Apple continued on without Steve Jobs is universally considered to be a major low point for the company.