There are WAY too many current and still ongoing series out that I love that I still wouldn’t have read if I waited for everything to be done. I mean, Dresden Files still has a half dozen books or something left in the series, and it’s been going on for around 16 years. Plus the Laundry Files, Monster Hunters International, Joe Ledger/Rogue Team International, the Rivers of London, and I’m sure more I haven’t thought of. I’m not waiting (in some cases) literally decades to start to read a series that interests me.
I agree. I’ve read a bunch of stand-alone novels, as well as series, and the series tend to be more enjoyable to me. Characters and story tend to get fleshed out more in series than they do in stand-alone books, at least for the ones I’ve read.