For some reason, this question gets asked quite frequently, so here's my take on the issue. If you're gluing properly, your joints will, once clamped, squeeze-out any excess adhesive you've applied to the joint prior to assembly. The old wisdom said that the correct way to deal with squeeze-out was to immediately clean it off the joints with a damp rag. Common sense should tell us that it's generally not such a swift idea to wet raw wood.
Wood is a natural, organic material, and it reacts, often quite frustratingly, to being wetted.
There are times when this is actually desirable, but most frequently it's just a nuisance. The other problem with this method is that it's darned near impossible to remove the glue with a damp rag. Basically, one generally ends up removing some of it, and smearing the rest of it around, eventually diluting it sufficiently that it seems to be gone, while it actually may or may not be. After frantically gluing, assembling, and clamping up a complex piece, the last thing your blood pressure needs is for you to rush around with a damp rag hunting down and killing little beads of glue. Have a cup of coffee.