it also changes as you add more line the more line the larger the effective raidus and the more inches per handle turn. With some of my older saltwater conventional gear like a penn 117 I put a bunch of thick string underneath my braid to increase the ratio of handle turns to spool turns. I became really interested in this when i started to get good at jigging because sometimes you want a jig to move slowly and if the reel retrieves a lot of line per handle turn you may have significantly reduce your retrieve speed. the other thing about it is that generally a lower gear ratio turns of handle to turns of spool the higher the torque or force you can use to horse a fish or even bend a hook! Abu garcia makes a reel called the winch if i recall the gear ratio is like 3:1 its made for moving the lure slowly but also for pulling fish out of cover. most spinning and bait casting reels are in the 5-7:1 range and that seems to work well for most fishers. when ever i see lower gearing i assume that its for heavier fishing like bottom fishing or tuna
"Even a fish wouldn't get into trouble if he kept his mouth shut." -Korean Proverb