There are those with far more than my 50-odd, but my answer is: I don’t.
Honestly, I rarely read the logfiles – only those where I’ve supplied a proper book when sometimes cachers write a little story. Sometimes people log with different names if they’re going as a group, or names are really hard to read (especially with some waterproof paper). For the first year of being a CO I kept all my old logs carefully, and filled up some boxes with them. Then I thought; “Why am I doing this?” and now I skim them and bin them.
Logs are there mostly as closure for the cacher, imo. I certainly enjoy the physical act of signing and dating. Sometimes to confirm if there’s doubt, too, but generally I take the pragmatic view.
I do delete the odd log, usually where somebody has logged twice, after letting them know. For some reason GS let this count twice, although the true count is still there on the stats, the main one is incremented by however many times somebody logs the same cache. I’ve spotted some cachers who make a habit of this and they’re total/ uniques are quite different.