You setup specific level design and have it all layered out the way you want it, you save the scene and quit for the night. A day or so later you come back to it, start up the editor, check your scene and notice a wall section or 2 are not at the Transform position (XYZ): 5.0; 0.2; 3.5, but is now showing up as 5.0; 0.20001; 3.499999e? Very annoying when it does this. I know it is so tiny and I will not notice but sometimes you can now see a tiny seam between objects, like walls and doors, etc. I also get this a lot with the Y position (especially after I dupe an object), where it is some weird real number like 1.973564230e-1 or something like that. Unity is going to be the death of me yet.