Actually no, bitcoins are created with a limited amount. The more scarce the amount will of course the higher the value, as well as the number of users and miner bitcoin the day progressively increases.
This is what triggers the bitcoin continues to rise, as long as not been depleted of course bitcoin will continue to rise in price although maybe in time will decrease.
But if all the bitcoin is already mined it could be bitcoin value will drop in the heyday. But hopefully not.
True about the limited amount and deflationary nature of bitcoin, but if it was just as simple as that then bitcoin would never fall in value, right? But it does. It all come down to supply and demand and unfortunately bitcoin's value is very psychological and is very prone to the attitudes of fickle people who panic at even the remote possibility of some bad news hence why bitcoin can drop in value quite rapidly so it's not always on the up and up.