[tacostakohashi]

Dividing and conquering where specific people are assigned specific source files / methods / etc can work well, and provide clarity to people who like that instead of expecting them to find / drive themselves.

Sometimes things are presented as a 'challenge' with 'points' and some prize in a lame attempt to gamify things. Pretending that it's not just work, and that a gift card will motivate people is kind of pathetic - it's just a normal part of software development work, the reward is that you get paid, and the software works and is easy to enhance and does what users expect it to.