Devices 75 years ago weren't designed to be millimeters thick.

If you have a removable battery, you need the walls of the battery to be thicker to prevent puncturing it. You have to have extra thickness for the battery cover and for the wall that goes against the battery. You need a contact interface for the battery instead of a flat flex cable.

There's no way to make an iPhone as thin as it is with a removable battery. You can argue that no one needs a phone that thin, but regardless, I don't think it has anything to do with planned obsolescence.

Limiting the product's lifespan is one rationale, but to say that there are no others is a little unfair. Off the top of my head, these are all within the realm of possibility:

- Easier/cheaper manufacturing process.

- Increased structural stability.

- Make the device smaller/thinner/lighter.

- Apple is concerned that end users will screw something up, so they want their service staff to handle battery replacement.

I'm sure the internal discussions that led non-user-replaceable batteries was more nuanced than "let's milk those suckers for all they're worth".

There will be a public rationalization for why they can't include an infinitely-lived battery, too. They'll probably say "power curve" somewhere.

I can't imagine that an iPhone with a battery door would cost more than pennies more to manufacture. iPhones are fragile, and have always been; if they can charge you $79 for a new battery, they can charge you $79 to fix the battery door. Smaller/lighter/thinner? You're talking a razor-thin space savings that adds up to a major inconvenience for users. Users have been operating battery doors for a very long time without electrocuting themselves or losing fingers. They're about as dangerous as an SD slot.

> I'm sure the internal discussions that led non-user-replaceable batteries was more nuanced than "let's milk those suckers for all they're worth".

I'm sure Snidely Whiplash doesn't work there. That a decision both so profitable and user-hostile was made is neither an incidental part of a general striving for perfection, nor undiscussed.

I worked on the iPhone at Apple and sat in many meetings where the product design and electrical engineering leads would almost come to shouting matches over fractions of millimeters. The engineering was fascinating. Everything inside the phone wants to be away from everything else. For example, the radios have power amplifier chips that are hot spots and need to be kept away from the battery to avoid exceeding its thermal limits. The antennas need to be kept away from noisy chips that would affect their reception. There are external connectors and SIMs invading the case. Once that is all crammed in, they need to drop test the whole thing and hope it doesn't bend or shatter.

It's really challenging to cram that much stuff into a constrained enclosure, and all of the layers add up. As I understand, a removable battery takes up a lot of area, because you need clearance below it and space for the mechanical fasteners. It also breaks up the pristine surfaces that are a big part of Apple's design language. The individual industrial design, product design, electrical, and RF design/antenna engineers responsible for each part aren't thinking about sales in two years. They want to make their piece as good as they can and hit the schedule.