Who said anything about crappy? High quality is achievable.
> If you do that, you've made a fragile piece of crap with no water resistance
As opposed to a fragile piece of crap with (some) water resistance? I'm not an expert on water resistance but I'm guessing something can be both resealable and water resistant.
> much less durability
Providing a back cover that would pop off if you drop the phone probably improves durability, due to the ability for energy to escape.
> Space which is in very short supply.
Why is it in short supply, other than because Apple tells you that you need a thinner phone?
Who said anything about crappy? High quality is achievable.
> If you do that, you've made a fragile piece of crap with no water resistance
As opposed to a fragile piece of crap with (some) water resistance? I'm not an expert on water resistance but I'm guessing something can be both resealable and water resistant.
> much less durability
Providing a back cover that would pop off if you drop the phone probably improves durability, due to the ability for energy to escape.
> Space which is in very short supply.
Why is it in short supply, other than because Apple tells you that you need a thinner phone?