What effect does it have on thin layer chromatography if the jar is opened during the process?

I had some really incompetent lab partners this past week and they kept opening the TLC jar to check how far the solvent had travelled instead of just looking through the jar....





So I'm including that in my errors in my report, but what kind of effect would it have on the actual outcome if the jar is opened? I know the system falls out of equilibrium, but what will that do to the substances travelling up the plate?What effect does it have on thin layer chromatography if the jar is opened during the process?
It shouldn't have much effect on the results, it's possible that it could have affected the rate at which the sample climbed the plate, but it's not likely that it would substantially skew your results. You lose more solvent because the vapor pressure is released each time the lid is opened, but like I said before, I would expect only minimal effects.