(I soon realised that this is not such a bad alternative activity because, slow as they are, snails do climb windows rather faster than paint dries, and that makes watching them a suitable form of recreation for those who lead busy lives and don’t have much time for fun.)
So, being an inquisitive sort, I naturally wondered why they do it. What are they looking for? What do they expect to find when they get to the top? Does the life of a snail hold some arcane purpose that makes it superior to the apparently purposeless life of a human? Probably not, but I chanced upon a theory.
I suspect they’re descended from an ancient species of snail whose natural habitat was the well worn pathways used by sabre toothed tigers, mastodons, heavily built humanoids and so on. In the sure and certain process that is natural selection, the ones that survived were those which confined themselves to vertical surfaces and so didn’t get trodden on. Hence the window-climbing genetic component became dominant. There.
An alternative theory is that they’re looking for God because no one has told them about Charles Darwin yet.