I wouldn't have thought to use that analogy, but I'm all too familiar with Ugh Fields. What's a shift in context for the same task? You re-weight the value of success and failure. When the activity was for fun, there was no real way to fail! Even naming the value of success can be hazardous - sometimes a person focusing on the "prize" of success will notice the other positive aspects of the activity less.
Personally, I've often found myself focusing on the prize most associated with the greatest potential losses. I went so far at the end of college as to identify success as the negative of failing. Perhaps it's something that happens when you fail a lot in sequence, and don't have time to re-evaluate goals. Making a desperate effort is not the best way for every person to be motivated. You build up negative affect for the activity or topic, if you don't get a good reward fast enough. Easier to think about the things that matter less - no loss, no stress.
If this rings true, then I hope you find an optimal strategy for dealing with it! I mentioned narrowing down the prize. When it's "work", I often find that I stop thinking about means as ends - the finish line is stuck in my mind, and the beautiful mountain trail is defined only by how inconvenient or hard it is. This might sound crazy, but I'd recommend making a solid plan that's much more ambitious than you need for your end goal, and then think about the end goal less often than you would normally.
I am realizing something that many, many intelligent people are guilty of - collecting and hoarding and accumulating crap, useless information. This is dangerous, because it feels like you're doing something useful, but you're not.
However, speaking personally - once I decide to start focusing and researching something systematically to get better at it, it gets harder to do. For instance, I taught myself statistics mostly using baseball stats. It was a fun, easy, harmless context to learn statistics.
I read lots of history and historical fiction. I read up lots on business and entrepreneurship. This is easy and fun and enjoyable.
But then, when I decide to really hone in, it becomes much harder. For instance, I'm doing some casual research on the history of insurgencies and asymmetrical warfare. This is the kind of thing I'd read all the time for fun, but now that I'm working on it systematically, it becomes a lot harder.
Likewise business and entrepreneurship - I read lots and lots on technology, financing, market research, marketing, etc. But now that I'm really nailing down one aspect for my next business, it becomes almost strenuous to work on that.
It's like... collecting and hoarding useless, unfocused information is for us what collecting and hoarding a bunch of useless consumer shit is for most people. I'd reckon that people that hang out here are smarter with money and less into buying junk, but, at least for me, I'm spending a lot of my time buying junk information.
Alright, back to reading about Tienanmen Square and Rome/Carthage and the Tet Offensive, and nailing down the buying criteria and budgets of the market I want to be in. Why it is so much easier to focus and collect crap mentally than to do it systematically on meaningful topics? Do you do this? I seriously doubt I'm the only one...