And I mean really, really lost.
A lot of people can't remember their passwords after 4 minutes since they set it up.
But apart this, there's several ways bitcoins can get lost, like in example if you have a wallet on a USB key and this breaks and you have no cold backup.
This will inevitably bring, in the future, to less than those 21 million cap.
And they WILL keep going down.
Is there a plan to reintegrate them?
At the moment, not. but It's just a consensus thing, and could "easily " be changed.
The divisibility of Bitcoins is how the lost coins problem is handled.
In short the money supply can be expanded by having the value of Bitcoin increase such that people will be urged to spend/sell to those the increasing demand.
I would NEVER agree to the 21M cap being raised and neither would anyone else who currently owns any btc
as it would signifigantlly devalue any benefits of being an early adopter and believer in this technology
To raise the cap to something like 21Billion for the saker of argument would make every coin worth 10 times less
how would the winklevoss twins and other large holders feel about that ? consensus lol ......i doubt it
people have also invested x amount because there will be a signifigant reward halving in 2016 and and the next one after that
when a steep rise in value is predicted ,to start monkeying arounnd with the coin supply now would just cause people to lose faith all together
since thats equivalent to irresponsible governments printing cash from fresh air now etc etc