On my journey in to work, I read a newspaper. A little old-fashioned perhaps, but both my parents worked as journalists and newspapers have been a 'given' as far back as I can recall.
I also read the comic bits, including Dilbert and the venerable Phantom, the ghost-who-walks. He is currently investigating whether an innocent person might have been locked in a prison. His search was cut short but today's piece, on his way out, he thinks to himself "I can't write that in the chronicles, that I checked every cell but one."
This is where quality, and expectations of quality, play an important role in what we produce. If we are working on a project or system that is known to be "trouble", there's the temptation to skip checking that last prison cell, to skimp on design or testing, to re-use/misuse an existing column or variable rather than create a new one, to not tidy away deprecated columns.
But when the standards are high, even or especially when self-imposed, you'll go to the extra effort to complete the job. When you've written your test cases BEFORE writing the code, you will test every one and you'll make sure they pass. If you do your test cases after writing the code, there'll be the temptation to test only what you know will pass. There's the temptation not to test a couple of edge cases you're not convinced will work, justifying it by the time saved that the consoling thought that "they probably won't crop up anyway".
So aspire to be like the Phantom, and hold yourself to higher standards.