An overflowing toilet can dump a lot of water on the floor and a bead of clear silicone caulk can keep that water from leaking into the wall and running down to a finished ceiling below where it can do a lot of damage.
Should wall tiles be placed directly above baseboard.
With walls this is also true but it is less important than with a floor installation where foot traffic is a constant concern.
Expansion joints in the floor.
If you replace the baseboards you can stop the tile about 1 4 from the wall and cover the gap with the trim.
Cut a piece to size with a miter saw.
If you tile up to the baseboards leave a 1 4 gap next to the baseboard and fill the space with caulk that matches the grout.
There are two reasons for this gap which is generally required by building codes.
You must be able to caulk the space between the wall and the ceramic tile floor.
Start directly next to a door or in a corner and measure the first line of baseboard or quarter round.
If you remove the baseboards another option is to replace them with matching bullnose tile instead of wood.
The baseboard at the bottom of a wall should always be installed slightly raised from the floor s surface.
If the tile floor is in a bathroom or toilet room then yes you really should.
Always install the ceramic tile floor before installing the wall baseboard trim.