3. Screen size
Nowadays, 27-inch and even 32-inch gaming monitors are becoming more common and affordable. An important consideration when determining the ideal size for your gaming monitor is the resolution.
If you have the same number of pixels for a 21-inch monitor as you do for a 32-inch one, then the pixels can look stretched on the larger screen, causing jagged edges on in-game objects and lack of definition that can impact your gaming.
Generally, if you are buying an FHD monitor, stay with 24 inches or smaller. If you want a larger screen, then QHD or 4K is the way to go.