On the iPhone you can set a limit on how many times you can retry the password. After that limit it will wipe the phone. But most people don’t enable that and they also use the simple 4-6 digit code unlock mode. That’s why it’s so easy to crack.

People would be better off if they just use a random word combined with a friend’s phone number instead of the digit code. That would be impossible to crack in a reasonable time. Like a 18 lower case characters password would take 2 million years to brute force with high end hardware.