Valve clearance doesn't generally get looser-noisier, with use, the clearance generally gets tighter-quieter, as the valves recede into the head as the seats and valve faces wear in. I've found particularly with the V-6 Hondas, that a valve adjustment at between 300-400 hrs very often makes them run a whole lot better, less noticeable with the three and four cylinder engines. If the valve clearance gets below minimum spec, they tend to be a little harder starting, and don't idle as well as a properly adjusted valve-train. Worst case, the clearance goes away completely, and it starts to burn the valves and seats prematurely because the valves don't shut completely. I haven't seen a single valve that was looser than max spec, and I've checked literally hundreds- but all my Honda experience is with the marine engines. I guess my point is that it's worth the effort to check/adjust the valve clearance, and always adjust them to the loosest spec.