Apple’s biggest mistake with the iPhone is probably the fact that it chose to keep it locked in the hands of AT&T for so long. The decision to bring Verizon into the fold does not seem to be having the once expected effect of drawing thousands of Sprint or T-Mobile customers over to the side of the iPhone. Even the iPhone 5, which will most probably be released later this year, does not seem to be powerful enough to sway users from other carriers.
There is no doubt that the iPhone is popular and many would instantly agree that they would rather own an iPhone than some of the other alternative smartphones on the market. However, very few are willing to risk changing carriers and are adamant that the iPhone come to them. Even Verizon does not seem to think that the iPhone would suddenly change the company’s fortunes by pulling in users from other carriers; it has big plans for android enabled phones.
However, do not expect Apple to suddenly part ways and make deals with alternative carriers, because there is simply not enough data to justify such large organization and logistical changes in its marketing and distribution. Therefore, the iPhone 4 and future incarnations of it will probably remain locked out for the foreseeable future.