What led to Kodak's collapse?

[PerfectClick]

George Eastman pioneered the use of photographic film and called his first camera the Kodak. It was first offered for sale in 1888. Sadly, a company with such a rich history stopped making digital cameras at some point. What led to its collapse?

 

[Len S]

One theory is that they didn't diversify. Just because the name says Kodak, that doesn't mean they cannot enter an industry that is hot with staying power.

 

[ClickExpert]

Diversification could have been the cause of Kodak's collapse. However, I think that there was more to it than this. Is there a chance that it didn't invest in research and development?