Um, that’s not quite right. Yes, many business applications can be served from off the shelf, but businesses also have internal processes that are unique to them. Off-the-shelf solutions may be able to adapt to these unique requirements, if they’re flexibly designed, but this can only go so far.
Of course, if a business is willing to change their internal processes, indeed, change their entire way of doing business, then off-the-shelf solutions may be perfect. What business is willing to do that, however?!