This!Reading a forum will give a false impression of “issues” as people only Post about issues.
Reading forums could also convince one they have to do a full device reset and set up as new for updates - a lot of very methodical and sometimes paranoid people who have much more time for device management than most users.
I've rarely had issues with updates, and then it's only nagging issues, not giant bugs. For major versions (say 14 to 15) I might give it awhile for bugs to be worked out, especially if they seem relevant to me. For minor versions I'm just paranoid enough to wait a day and see if any major bugs crop up. If there's a huge issue like a lot of devices getting bricked or the phone sending out your entire photo library to all your contacts or whatever, the update should either be pulled back or revised within that time.
There are over a billion active iPhones. Tens of millions (or more) of those will have updated within the first day of an update being released. Apple is also one of the most-watched companies in the world. If there's a major breaking issue with an update, it's going to make headlines, and you're going to know beyond a doubt whether or not you should update or hold off within the first day. There's always a chance something could go wrong, but it's statistically improbable.