It’s important to understand what’s important in regards to exactly how the cut tile should surround those outlets.
The key to understanding how to correctly mark and cut your tile starts with the plug or switch itself. If you look closely, you will see the top and bottom sections of the plug or switch have a metal tab. Within that tab is where the mounting screw is located. This screw connects to the electrical box that is mounted in the wall. You can also see what we call “ears” or the very outsides of the plug/switch. Those ears need to be able to rest against your tile.
Here is the idea: As the mounting screws are tightened, the plug/switch is drawn to the electrical box and eventually will come into contact with the tile. This secures the plug/switch by the pressure that is created by tightening the mounting screws. We don’t want to over-tighten and possibly crack the tile. A snug fit is all we need.
A common method I have seen is when the tile is cut completely around the entire plug/outlet. You will then need to use a plastic spacer that is used in place of the above mentioned.
Both ways work, And acceptable. It’s more of a preference. I am comfortable using my method mentioned and have been doing it that way for many years.