I think the general idea is "shift left" which you can say exposes bugs earlier, or prevents bugs from reaching production, which is kind of a "six dozen of one

I think the general idea is "shift left" which you can say exposes bugs earlier, or prevents bugs from reaching production, which is kind of a "six dozen of one, half dozen of the other". Bugs which are exposed early enough do not get committed. "Shift left" just means that you shift the feedback to the developer farther left in the build process, closer (in time and space) to when the mistake was made.