Does adding water during bleaching damage hair?

Dear Beauty Brains,

I am bleaching my hair with powder almost every month and never had this issue with my previous hairdresser. But I had to switch, and the new one spayed my hair with water after keeping the powder on my roots for about 40 mins. When I asked her why she did this, she said that water keeps the bleaching reaction going. However, no one ever did that on me before. I’ve also heard somewhere that no water should be added during bleaching, that it affects the hair negatively.
Please help me find the real deal beneath this water+bleacher thing.
Thaks a lot for your outstanding job)