Who can tell me why we should stick to the wall?

Several purposes. Waterproof glue 1 can ensure that water vapor does not enter the tiles below to avoid water leakage. Because water easily penetrates between the wall and the ground. 2 beautiful. If you don't glue between the walls and bricks, there will be a deep underworld in three or four years, and all kinds of dirty things will penetrate into this gap, which is unsightly and unsanitary. 3 hygiene. The purpose of gluing is actually that the nature of the baseboard is basically the same. At the same time, it is also necessary from a health point of view. 4 durability. The life of glue is long and short. This kind of glue can last about 150-20 years, so you don't have to worry about it these years. 5 save money. Do you know how much time and cost it takes to clean up the underworld? Clean it once every 1 year, each time 10 RMB, increasing by 5 per year. Do the math. 6 textured paper. Its efficacy is mainly reflected in beauty. A wall brick, a floor tile, the glue between these two roads. Some workers are lazy and don't use textured paper. It's ok, but it's over. It's like eating by a dog. You paid for a beautiful woman, but it was made, not bitten by a dog.