I delete on a regular basis. Sometimes a Hub seems like a good idea for the moment and later just doesn't. So, I'll usually do something like delete three when I've got two more - or something like that.
Just now, though, I've been getting ridding of some of the "Zz'd" Hubs. Although some of them could probably be fixed, some of the ones I have really don't deserve the light of the day. I've been on here for awhile, and up until fairly recently I've never really known what I should or shouldn't be writing. That's become clearer over the last year, so it's also become clearer that some of those awful Hubs don't belong here. I don't really have the subdomain in mind. For the most part, that doesn't do too badly (considering the kind of stuff I have on here). It's mostly that the Zz's called attention to Hubs I haven't given much thought to. I'm pretty slow to remove Hubs because some can surprise you, but the ones I'm deleting aren't doing me any good on here (and it isn't surprising for most of them). What I find with my own Hubs is that the ones nobody else seems interested in are also the same ones I recognize as "bad", deciding to delete isn't a big conflict for me. I don't do anything hasty, though.
In answer to your question, I'm not sure how many Hubs I've written "in all time". I do know I knocked about 350 Hubs down to around 320 over time. Then I knocked those down to 300. I'm now in the processing of dealing with 20 or so remaining Zz's. BUT, crud or not crud; I do save everything I write (and then delete) in case I may have some use for all or part of it in the future, somewhere else.