There's this software that one of my customers use called SAP Fieldglass. Fieldglass was a separate company and sold for $1B and it might be - and I'm not exaggerating - the worst software I've ever used, pretty much ever. But the reason is interesting. It's designed as enterprise compliance software and nobody enjoys using it. The enterprise managers hate it. The vendors hate it. The contractors hate it. The finance team hates it. I can't imagine anyone enjoyed writing it. The UI is unintuitive and self-discovery is practically impossible. It's so bad that companies have resorted to making Youtube videos on HOW to take repetitive actions inside the tool. The system is so anti-success that part of me wonders if this is done on purpose; to delay any kind of payments to vendors / etc.

The best part is it doesn't _do_ anything itself. It's just a workflow system for dispatching operations to different systems and teams. It will create an invoice in an existing finance tool. It will issue a ticket to create a physical badge, etc.

Anyway I think that's a massive opportunity, if that's what you're looking for.