The problem is that people aren't willing to pay very much for a patent application, and so the drafter doesn't really have enough time to scrutinize every sing

The problem is that people aren't willing to pay very much for a patent application, and so the drafter doesn't really have enough time to scrutinize every single word. It's not at all uncommon to spend 100 times as many lawyer-hours litigating a patent as you spend drafting it.