If no adhesive is applied then the tiles will fall off.
Tiles popping off wall.
Adhesive has not been applied properly.
Continue removing tiles.
Quickest way to remove wall tile 1.
Remove all the tiles in that vertical row by tapping and prying with the putty knife.
Where the tiles are showing this issue is not where the shower is.
Only mix enough thinset as you can use in one hour or less.
Once the first tile is gone.
Tile can swell with high moisture absorption.
If you have used poor quality adhesive.
Break the grout around a tile in the middle of the wall with a stiff putty.
Only apply as much thinset on the wall as you can cover with tile in five minutes.
Make sure that the tile adhesive that you use is water resistant.
Use cold water to mix the thinset to retard the setting time.
Why would you need to seal white glazed tiles for bathroom use or grouting.
Put on protective eyewear and gloves.
If the gaps are not consistent during the expansion phase the tiles will not have enough space to release stress which results in tiles popping out.
Grouting has been done too early.
The chalk dust will stop the tiles from adhering to the wall.
Do not add water to the thinset if it starts to get hard in the bucket before you spread it.
The adhesive needs to be applied evenly and on every tile.
Due to expansion the pressure will cause the tile to pop up.