Can water cause fermented pickles to spoil? I recently learned about Indian lemon pickles. 

There is a lot of variation between recipes but the ones I am trying consist of chopping lemons or limes, adding salt, and letting them ferment for a period of time before adding spices.



A large number of recipes have included a warning that the lemons, utensils, and jar must be completely dry or else the pickles will spoil quickly.

Here is one example
"Even a small drop of water makes this pickle spoil soon."

This doesn't make sense to me for several reasons:  


There is, of course, already water in the fruit
A tiny amount of water won't be enough to significantly dilute the acid or salt
I have never seen such a warning in fermented pickles from other cultures


Admittedly none of these recipes have come from an authoritative food chemist. They are all traditional recipes.

Can water actually spoil fermented pickles or is this an Indian old wives tale?
ANY amount of water on the jar or the ingredients does result in the formation of whitish fungus at the affected spot. This will later turn black and the pickle will sour giving off a fermented smell. 

The only exception is if that spot is well immersed in oil- but no guarantee it is off!
The "water" in the fruit, being juice, fights formation of fungus and mold.

I'd tried to cheat but the punishment by the pickle is heavy!! -and I am a cookaholic going on 60 years.

Note: This precaution applies especially to hot climates where the reaction is in hours and max in a couple of days--- hv observed it in u.s in Florida and California.
Try your bravery.