"You don't upgrade your toaster, do you?" -Steve Jobs (supposedly, infamously opposing any kind of upgrades, slots, etc. for the Mac)

see also: https://www.folklore.org/Diagnostic_Port.html

Steve immediately nixed his proposal, stating that there was no way that the Mac would even have a single slot...

He would also rather have them buy a new 512K Mac instead of them buying more RAM from a third-party

The more things change...