Why the minimum screen lock timeout is only 30 seconds?

“Immediate" would be pointless; it would lock as soon as you unlocked it, so you could never use the phone.

5 Seconds means that you would have to unlock the phone and then choose the app you wanted within 5 seconds, and if you didn’t use the app continuously it would lock in the middle of what you are doing.

Perhaps you aren’t thinking of Auto-Lock, but actually Require Passcode, which is how long after the screen locks you can still unlock it without entering a passcode or Face ID. If you have Face ID enabled, that is always “Immediately”.

Auto Lock will lock the screen when no taps are detected on the device. If it was 5 seconds, you would not even be able to read a text message or web page before it locked. To immediately lock your screen just click the side button.

Ever since I turned on auto lock to never my phone doesn’t turn off when it’s turned around and I feel like 30 seconds is more than enough time to snatch a phone and go through it. I can’t go to work and keep my phone there without it turning off I just want to be able to have my phone there and not get it taken and or looked through by a random person.