If we reward programmers for each pull request they merge or for each ticket they submit and we don't control the quality of PRs and tickets, what will happen? Nothing good. They will easily abuse the system and there will be tons of low-quality tickets and PRs (or classes, or lines of code). However, if we do have strong quality control, everything will be just great. Thus, when someone says that paying per line of code will ruin the project I answer: "Only if your project is weak".

The video is here: https://youtu.be/JIspFqjRt80