Slow responding applications could be a nightmare.
Imagine that your customer sits next to you while you try to open his new account. You pressed the “Create Customer” button and expect that a few seconds later their account has been created. Surprisingly, after 60 seconds there is still no confirmation available and your Create Customer process seems to not respond. This is a very inconvenient situation because you will loose confidence of your new customer and in worst case you will start the whole process once again including the insertion of the customers details.