The difference in gear ratios in tuners?

I was deciding to buy a new set of guitar tuners. I read about these "ratios" like 14:1, 16:1, and 18:1. The ones I'm looking at are Gibson Grover Nickel Keystones (not the vintage ones with the plastic tips, The ones with ALL nickel like a regular Grover.) These I'm looking at are 14:1, and I was told that the ratios are kinda like what make them "slip" less or more. Does that mean the strings will go out of tune with the lowest ratio and they will stay in tune with the highest? What does it mean necessarily?