youre talking about the value of each bitcoin infinitely rising. like in 15 years each BTC worth 28.783 million dollars, and my coins appreciating in value .5% in the time it took to pay for my coffee.
somehow this seems unlikely.
This time your question is not clear...
If in the future there is 3 billion people using bitcoin for day to day activities, there will be a significant portion of the finite amount of coins constantly flowing into various governments tax coffers and temporarily (maybe) being taken out of circulation. For it to be a viable payment system for everyday use, the value of each coin would have to constantly be on the rise to account for the large amount of them being taken out of circulation.
I should also say that I don't believe bitcoin will ever fully replace the fiat system, at least not in the next 100 years