I always start a Minesweeper puzzle in Windows by clicking the cell in the lower left corner. Even though I have never seen a bomb there, how sound is this strategy? Is it possible that some time in the future there will be a bomb there? Or is it possible to click anywhere the first time?
Many Minesweeper games, including the one that ships with Windows, do not allow the first square you click to be a mine. The lower-left-hand corner is not necessarily safe, but if it's the first square you click, then it will be safe.
In at least one version of Windows (I think it was XP that I tried this on), Minesweeper ships with a cheat code that allows seeing whether a square has a mine or not by hovering the mouse on the square without clicking. I once used this to mark every mine on the board before clearing even the first square. I then clicked on one of the known mines. That one mine was moved, but all 98 other mine markings proved still accurate.
The board is generated before you start to play, but the first square you click is forced safe regardless, even if that requires relocating one mine.
Since the cells adjacent to the corners have only 5 cells surrounding them, and because the algorithm that means you usually will have bombs next to each other, the minimal amount of cells touching cells creates an area where bombs are less likely to appear. It is also a good strategic move because the cell (if it is not a bomb) will say 1, 2, 3, or 0. 1 gives you a 0% of knowing where to go if you click on it, and 2 or 0 gives you a 100% of knowing where to go if you click on the corner cell. And 3 is a 33.3% chance. Add that up and you get 70.8% of knowing where to go. Cells not on a corner but touching the edge: 54.7%, and cells in the middle: 41.3%. Going in the corner is a good first move in Minesweeper.