Common Mistakes and How to Avoid Them
Traps that beginners often fall into.
The most common mistake is hastily opening a cell that isn't confirmed. If logic hasn't proven it safe, look at another border first.
Chording while a flag is misplaced is also dangerous. Running a chord from a wrong flag position opens even unsafe cells, and a mine goes off.
You can also lose the big picture by fixating on one spot. When stuck, widen your view and check another border or the total remaining mine count — new confirmed cells will come into view.