I don't know if I can speak for other Dominants, but how I feel about it is pretty simple:

If I was in a room of a bunch of subs (which for me would be guys but I don't think that matters, really), all wanting my attention, begging, pleading, grovelling or whatever, those things are nice, but the one who catches my attention is the quiet one in the corner. Eyes downcast at my feet, not my face, totally ignoring whatever else may be going on as his full attention is solely on me so that even if my back is turned, if I beckon him with the slightest wiggle of a finger, he'll silently crawl to me and wait patiently for directions, whatever they might be.

That is what submission means to me, anyway. Complete attention and patience; a blank slate for me to write on.