@bythewell - I think it's that blockbuster mentality that causes software crises. Companies think if they don't manage to get to the number one spot they will quickly be replaced by something else. They don't want to maintain old software, because there's no profit in it.
This is why I think that freeware and open source software is the way of the future. It's done for the love of it and maintained for the love of it, rather than for profit.
Which is not to say that they can't suffer from a software crisis as well, but at least they aren't using up lots of money when they do so.