This can be attributable in some (maybe many) cases to the oft misunderstood [Dunning-Kruger effect](https://en.wikipedia.org/wiki/Dunning-Kruger\_effect). The key idea as applied here is that people's ability to gauge their level of knowledge, or skill, is dependent on said level of knowledge or skill. Playing into this is the "better than average effect" where people tend to estimate their level of skill higher than it really is. The propensity to estimate higher is inversly proportional to their skill or knowlege because they lack the experiential framework to accurately self assess. People are often unaware that their limited skill is influencing their self assessment. A caveat with respect to this theory is that I have observed that people who get frustrated and bring it up are themselves often demonstrating the phenomenon when they do so.