How do you know that after you have your farm grid, zoned or whatever method you decide for sampling that the results are accurate?

Case in point I had 80 acres sampled that had been grided 4 years ago and it needed lime which was applied, resampled this year and it called for 2 and 1/2 times more lime than was applied 4 years ago. When I questioned the results I was told that's what the maps called for and that's what I better apply, didn't matter what was applied in the past. Then we went thru the grid results and found that the soil types didn't make sense in the one corner of the field. Dealer made some calls to the lab and found that some of the data was improperly inputted to the maps (icesolated case, yea right!!!). Long and short of it was the lime recomendation went from 210 tonnes to 54 tonnes for the field.

In my case I have just a basic understanding of soil test results, not like some of you on this site and I rely on the supplier to read the results for me, how do you that what you see is accurate or what you are told is right?