So, as an example, someone finds a flint and claims it was a Neolithic cutting tool but a very basic one with no extra knapping being done on it. By chance I find the very lump of flint it came off so whack another bit off that also looks like a cutting tool. Put alongside the other one and they look more or less the same same. They are the same age of course as they came off the same lump, but would they both be claimed as a Neolithic cutting tools if mine was tossed on the ground alongside of it without anyone noticing? It seems to me that a lot is taken for granted in flint discovery sometimes!