I think the big thing was Steve did make a lot of great decisions, some of the best the company could at that time in those respective fields but completely missed on everything that Apple did. Portable media players, smart phones and tablets and those are the three huge misses and that is really were it counted.

The old three envelope joke.

You become CEO and there are three envelopes on your office desk, a note says "Every time there is an issue you open them in order and do what is inside". First envelope says "Blame your predecessor.". The second says "Blame yourself". The third says "Prepare three envelopes".