I live in a second floor flat with a balcony. Today when I was getting DS's trike from the balcony to take out to the park, I noticed that some rainwater (maybe 1/2 to 1 cup) had gathered in the bucket at the back. So I did what I always do, lift the trike up, lean the whole thing out over the side of the balcony, and gently tip the water out on the bushes.
Cue 2 minutes later neighbour downstairs knocking on my door to complain that I had drenched her plants on her balcony and this was going to kill them.
Errr WTF? I was polite and apologised but pointed out I wasn't trying to get water on her balcony, I just didn't have any other way of emptying this small amount of water out of DS's trike bucket, and it was... errr... water. I said I would try and avoid dripping water on her balcony when I occasionally did this, but it was a bit hard.... but I did reassure her I wasn't trying to damage her plants 
She doesn't have particularly unusual or out of the ordinary plants on her balcony. All of the balconies in our building are north facing, very exposed, get a lot of rain (where I live is permanently damp and drizzly). In fact I don't have any plants on my balcony anymore because they all got waterlogged from so much rain and died because of the cold/lack of light!
I do think she is being a bit precious. It's not like I'm getting a big full household bucket of water and tipping it right onto her balcony. Her plants might have been hit with say 1/3 of a cup of rainwater.... and that's what is apparently going to kill them. 



AIBU to think that you should know that water is wet and if you put plants on your balcony they might get.... wet?