Has anyone come up with an effective solution to this problem?
There have been studies. Intrinsic motivation is always better. That said, if intrinsic is missing, for extrinsic, they say rewards should come often and timely. Eg, giving $100 for passing a midterm is not as effective as $10 for passing the weekly quiz.
To help myself accomplish tasks I’m not interested in, I leverage the rule of threes. I set 1-3 accomplishable tasks for a time period (say before lunch). Instead of “rebuild a deck,” I have much more fine grained milestones: tear out the old deck, take old debris to landfill, level the ground, place footings... The reward is moving onto the next task. By limiting how many projects I have, I don’t get to start a new one until I get something else “done enough.”
Some examples I’ve heard from others where external rewards helped: someone would buy the next $item in $set (game pieces for a table top game, or car part for a restore, or anything that let them do more with a hobby), would add $funds to $project (dollar in the music instrument fund, n minutes of video games, time to decompress), and my favorite, they would do something nice for someone (write a quick love note, or let someone know you appreciate them and why, a small compliment; give themselves the joy of helping others).
While dieting I had cheat days. But that was never a lifestyle that stuck. The only thing like that that stuck was a slight change in timing and veering towards less sweets and booze.
The only thing I've found compelling is my own internal drive and sense of accomplishment.
The best thing I’ve done is break up the work into smaller milestones and get regular feedback from a stakeholder.
Feeling I’m making progress will be a reward in itself, but also the feedback will help steer the direction of future steps. It saves more face if it’s noticed earlier I'm not well suited for the task rather than letting it drag on.
This applies to any kind of work. Even if I’m taking on a home improvement project I can ask my wife what she thinks of my progress thus far and get a sense of how I should adjust course (up to giving up and calling an expert).
I recently picked up a nice friendly clock for this: https://www.amazon.com/KeeQii-Minute-Visual-Silence-Countdow...
I liked this as it was easy to see how much time there was. I avoided the red one as I found the blue to be more peaceful. So I have one at home, will buy another one for work.