Homework
Most jobs, in my experience, don't require market segment understanding. I wrote an internal app for K-Mart that integrated with their inventory management system; I didn't need to understand consumerism or how they targeted their advertising. I wrote backend code for Bloomberg, and while it was handy, perhaps, to understand some financial market details, it strictly wasn't necessary. I wrote some Bluetooth integration code for an internal app at Chick-fil-A; I really didn't need to know their menu.
However, in the K-Mart scenario, understanding the end user (employees) was important because it influenced the decision on how the user interface was designed (to mimic the system it replaced). At Bloomberg, knowing about commodity exchanges was useful when communicating with the team in charge of those data streams. The broader context at Chick-fil-A had to do with over-crowded drive-thru lanes, and it was very useful to see that first-hand to understand the employee challenges.
None of that broader context information was personally useful though. Is K-Mart even still around? I don't care about corn futures. I don't use the drive-thru lane ever – on the rare occasion I eat out – but I'd probably be a little bit prideful knowing my code was speeding up the line, so there's that.
Now I'm learning about heath – something, as a living person, I should know plenty about already, but I don't. My work life is bleeding over into my personal life in a mutually beneficial way, and that's a refreshing change.