In chemistry etc the properly-kept lab notebook is also an almost chain of evidence thing, both for scientific (integrity) and commercial (patents and such) reasons. I.e. never erase, only strike-through so previous error is still readable, numbered pages, each section dated and signed, properly kept index, ... all make it a lot harder to falsify things after the fact. (Nowadays there are also digital record-keeping tools that do timestamped signatures and such instead)