The passage of water through the semi-permeable membrane is controlled by either the TDS (total dissolved solids) or EC (electrical conductivity) of the nutrient solution. So, if the EC of the solution you’re feeding is excessively higher than the EC currently in the roots(soil,hydro), the plant can dehydrate by drawing water out of the roots and into the medium via osmosis.
The best defense against nutrient lockout is to routinely monitor your nutrient solution at the reservoir topping off as needed and flushing every two weeks.
If you're medium is soil.. check your run off PH level.. meaning, PH the water that comes out of the bottom of the pot and make sure its as close to what it went in as.