De minimis non curat lex
the law does not concern itself with trifles
Where the phrase comes from
A maxim used to ignore harm that is truly trivial. It is not a defense to every small-looking claim.
What lawyers are pointing at
Trivial is about the law's interest in the harm, not about whether the claimant is annoyed. A few cents can still be a real overcharge if it is systematic. A fleeting technical trespass with no damage is the kind of fact pattern where the maxim is actually discussed. Quoting it to wave away a breach you would not accept if you were on the other side is an abuse of the phrase.
The same shape in code
A one-byte difference in a rotated log name is a trifle. A one-byte difference in a payment amount is the whole defect. Count the effect, not the diff stat. Teams that call every bug de minimis are using the maxim as a mute button.
A concrete picture
A boundary fence that sits one inch over the line for a week, with no use of the strip, is the sort of fact the maxim was meant for. A one-inch encroachment that takes a load-bearing wall is not.