Bottom layer vs top layer


Each number on the block represents which game layer each one belongs to. This picture shows that I do not understand flowlab’s layer mechanics or this is simply a bug. Layer 3 seems to be the highest (there is a 1 underneath layer 3 btw), layer 2 the lowest, and 1 is the middle level. Wouldn’t it make more sense if Layer 1 was the lowest level, layer 2 the middle level, and layer 3 the highest level? So this is either a bug or I’m not understanding what each layer is supposed to be used for. Someone correct me please?

The layering should be 1: lowest, 2: center, 3: top. Can you send me a link to this game? You may have found a bug.