I learned this early on, also. I'm always amazed at people that put their bid in with 3 days left. What good does that do? It just drives up the price.
One idea being bandied about - in a "real" auction, there is no time limit, within reason. If bidding is active, then an auctioneer would be silly to stop bidding at a predetermined time. So, it has been suggested that as long as a flurry of bids is coming in - then the auction should be extended by a few minutes, and hour, whatever. "Sniping" takes advantage of the fact that an eBay auction ends at a specific hour, minute and second. I have won a few auctions within 1 or 2 seconds of the ending time. It just has to really crank the poor guy who was #2, but Oh well.
I bid early if it's something I'd pick up if I ran across in a yard sale, but which I'm not exactly pining for either. If someone wants it a lot more than me, they're welcome to have it. I won't be watching the clock.
For the more expensive items, though, the stuff you really want that's hard to find, then no question ---- I'm on the computer at whatever ungodly hour that thing is ending so I can slam my bid in inside of the last 10 seconds. The priciest thing I ever bought on eBay was a set of an author's "Works" for $450.
A low-ball bid on eBay is like a self-ping on FR. It flags it for your watch list.