Significance of average block generation rate I am stuck in this thought for a while regarding the block generation rate. My concern is, when a payer waits for 10 minutes to confirm that her transaction is included in a block, it suggests that a new block is generated in 10 minutes, because her transaction is brand new and the block includes it. So, how does a miner do that in just 10 minutes? Isn't it supposed to be hard? The miner can then become a millionaire in months.

Does the block generation rate imply that, once a miner starts computing the proof-of-work(POW) she succeeds in getting the nonce after 10 minutes? Or is it the case that miners are computing POW at their own pace(probably for a long enough time) and 1 new block pops up every 10 minutes. If the 2nd scenario is true, how does it justify the waiting time?

Thank you.
The block difficulty is adjusted every 2016 blocks so that, on average, it takes 10 minutes for miners to generate a new block. It would take any individual miner much longer than 10 minutes to compute the proof-of-work, but all miners together should be able to compute the proof-of-work in roughly 10 minutes.