Bitcoin is essentially deflationary. If Bitcoin maintains its utilitarian value, it will only grow in monitary value since less and less coins will be minted until no coins are minted, and also as people lose access to their keys.

I speculate that in the future, Bitcoin might become valued so highly, that people don't even bother using it in favor of other coins, and as people don't use it, no one then accepts it, then it loses value, and by then people are accustomed to using other coins, and Bitcoin dies. Who knows, I probably won't live long enough to see it.