Finding the next block is a random procedure. Miners try to guess a number that 'solves' the block puzzle. It could take 2 seconds or it could take 30 minutes.

Finding the next block is a random procedure. Miners try to guess a number that 'solves' the block puzzle. It could take 2 seconds or it could take 30 minutes. On average it takes 10 minutes. Faster computers can try more numbers but slow computers have a chance too. The faster your computer the better your chances. Does that make sense?