Does flashing incorrect ROMs or changing the partition table ever result in damaged motherboard components?
This sounds like the device has one drive with separated partitions for system, data, etc. ...

If you flash the wrong rom, it will change the partition size to be different than the original...

For example, 2gb ram will be overwritten with 3gb ram... This makes 1gb less space for the system or data, And potentially overwrites the existing data ... You might accidentally overwrite the modem files with ram space ... and so on ...

Usually you can partition SD Cards for different devices, but Partitioning the system isn't advised !