I'm not talking about tiles, which so 60's. I'm talking about a nice floor to ceiling (or however far up you want to take it up) mirrored
*wall*.Also, it's not just tiles that point out that a wall isn't flat, you have the same problem with big plate glass mirrors. And the mirrors aren't perfectly "flat" either.
If you are butt joining the mirrors and not covering the joints with bevel strips, you have to use a suction cup to pull and push the mirrors to get the edges flush.
IOW, you have to work the mastic on the back of the mirror to get a perfect butt joint.
Some installers take it so far that they use a level on the surface of the mirrors to get them perfect so there is no "distortion" while looking at the mirrored wall.