When you loses wallet, it has the effect of removing money out of circulation. Lost bitcoins still remain in the block chain just like any other bitcoins. However, lost bitcoins remain dormant forever because there is no way for anybody to find the private key(s) that would allow them to be spent again. Because of the law of supply and demand, when fewer bitcoins are available, the ones that are left will be in higher demand and increase in value to compensate.
This is one of the disadvantages of the bitcoin that it will going to stay forever in the block chain and gone if we lost our private keys therefore we should to take care of our keys to avoid this thing to happen unlike fiat that even the owner will lost or dead still the physical money exist and it can be use by the charities. We just hope that block chain specialist could do a programs in which it can trace the inactive or floating wallets to recover it like what they do in SegWit programs.
because the average owner of a bitcoin purse in which it contains bitcoin would not have allowed his private key to be known to others, as they would be safe, their passwords, one way of avoiding bitcoin to be stak, is to have an associated heir personal key data of bitcoin wallet.