difference between nute burn and defecency

I see all these pictures posted and the replys given,,my question is,,they mostly look alot alike and some say def. others say burn,,are there any telltale signs of each? i know i posted before and was told to feed they needed nutes,,then others said no its nute burn,,,have several plants and have tried different things when i get responses,,one plant all said to feed so i did,,with only 1/8 dose,,ended up with worse nute burn ,,posted pics of another that was similar to first,,got responses that it was nute burn so i flushed and layed off any nutes...still had same problems...if there are any factors to look at for each,,( burn or def,) would love to know.

Sometimes you can get nutrient lockout from heat or other problems where the plants can't absorb various nutrients in the soil, despite the soil having plenty of nutrients. People think it's a deficiency so they add more nutes to the soil, when the real problem was heat or something else...

There is no way that feeding a plant 1/8 of the recommended dose will burn anything ,its not nute burn, where are the pics ? could be anything.
why the double commas ? do you stutter?