This is pretty wildly inaccurate specifically in Project Farm's case. Most "consumable" parts of tests, like bolts, are swapped out from test to test. From what I've seen he's pretty transparent when that's not the case.
He also explicitly buys all products with his own money (some by way of viewers contributing, of course) and products are sourced from what folks in the comments are asking for.
Scientifically, one should test multiple “identical” components for each test and average the results (or do something like a box and whisker plot) to incorporate manufacturing variability.
But his results are authoritative as the bar is low.
He also explicitly buys all products with his own money (some by way of viewers contributing, of course) and products are sourced from what folks in the comments are asking for.