After the success of the Genesis / Megadrive, Sega made two addons which sort of flopped, the Sega/Mega CD and the 32x. With the release of the new 32-bit system on the horizon, people were hopeful. But it seems SEGA undercooked it in a few departments, causing issues that would lead to their downfall as a console maker.
Here's what those issues were, both with software and hardware, along with what changes I would've done to fix it.