[Tycho]

To maintain a monopoly in itself would be expensive and not necessarily the way to maximum profits (there is always the threat of outside investors). Innovation of course costs money but if a company remains stagnant (because its profits are unaffected by competition) then it runs the long term risk of becoming obsolete when substitute technology comes onto the market. You could say competition is a short-term cost but non-competition is a long-term disaster.

In Apple's case, though, there's already plenty of tough competition going on.