Until the users want a new feature - save/load, say - and you can't add it without breaking the toaster in the office kitchen. And so the users bugger off to play Candy Crush Massacre or whatever :-)
The newest SimCity is a great example of this.
"zomg offline mode should be really easy for you guys to write! Why haven't you yet!?" "well... ...technical debt and design decisions that are at odds with that..."