Amplification will not always improve speech discrimination affected by a sensory neural loss.
There are many causes of sensory neural loss in infants and children.
This includes viral infections of the mother before birth or the baby after; blood incompatibilities between the baby and the mother; medical or pleasure drug effects; oxygen deprivation; physical trauma; genetic inheritance; and noise pollution to mention a few.
Young teenagers who play in rock concert bands are particularly at risk for noise pollution.
A consequence of the unevenness the a sensory neural hearing loss is that one cannot guarantee that amplification will be beneficial in every case.
In some cases it lowers the threshold level so that consonants can be discriminated and speech discrimination improves. In others, consonant discrimination remains poor and the person is blasted in the lower frequencies by the amplification. In some cases the discomfort must be weighed against the gains.
NOTES: Here is some interesting information on noise pollution.