This might have been answered elsewhere but couldn't find it, if it has.
The miners get paid less and less as time goes on.
With the ledger also growing bigger and bigger, wouldn't the cost of mining start to exceed the profitability of mining? If no one would mine bitcoins anymore, wouldn't it shut the whole system down?
THis is exactly part of what drives price up. If profitability of mining is too little, miners would drop. There's increasing concerns about the effect of BTC due to its carbon footprint, this way there's a balance between viability and power consumption. Currently there might be more miners than necessary, but eventually even that will level off as well.