iOS is lacking in a lot of features. I mean you can't even change the notification sounds for heavens sake! If you've ever tried to type long posts/emails/texts on stock you know how hard it is to edit text on stock. With a jailbroken phone I have access to tweaks like SwipeShiftCarat, Delete Word, OctopusKeyboard that make the typing experience soo much better. You might argue "we'll I don't need to use that stuff because stock is safe and secure" but then you're bringing your personal views in an argument instead of focusing on what's actually being discussed. I can also argue that stock isn't always safer, just think about the lock screen bug that was patches up. If apple ever implemented a security feature the likes of iCaughtU Pro it would hands down make it the safest phone in the world. The features in that tweak are limitless alone.
A person who knows that they are doing and doesn't install random tweaks, repos, and doesn't pirate apps/tweaks (I've bought all my tweaks over the years and I'm proud to say that) I don't have random crashes, resprings, bugs happen to me. In fact, I'm confident enough jail tweaking I offer help to many tweaks who need beta testers, like Copic, BatteryDoctor, BattSaver, ISX, and the list goes on.
Yesterday my co worker saw my ISX build up on my phone and said how I did that. I told her I jail broke my phone and installed some tweaks. I showed a list of thing I can do that she couldn't do stock. I also informed her that most of my tweaks were paid for and she still asked me to jail break and install the main ones, like bitesms, ISX, Copic, and ad blocker. She hasn't told me any problems as of yet and i don't expect to her from her about these problems. If you install tweaks that are supported and made well, you won't have any problems.