[djhworld]

> on top of that a SIM can store your contacts (up to a certain number).

This presented a usability nightmare back in the days of feature phones, where if you didn't specifically say where to store contacts, it would often default to the phone's storage rather than SIM, or if you breached the number of contacts on a SIM you'd have overspill onto the phone memory (sometimes without realising)

This presented a lot of unnecessary confusion when it came to upgrading devices, or if you damaged your phone.

[WatchDog]

Well by the same token, sims offered a simple way to move contacts between devices, which was otherwise difficult to do without a pc and proprietary cables/software to export data from the phone.

[shavingspiders]

It still is an issue - carriers (at least in NZ) still ask you if you've backed up SIM contacts before switching the phone number to a new card.