Clipless peddles have moving parts, and moving part collect dirt & debries. Air in can like you use to blow out computer keyboard helps blow out dirt, etc.

I use a Look Delta Peddle, and use Bee Wax on the back surface of the cleat that is what comes free when you kick out.

Call me anal but every time I come home I take an old rag get the gunk out of the peddles, use a drop of white lightnig on the moving parts, than dry the excess with a q-tip or rag.