What would happen if nerves didn't have refractory period?
Refractory period returns the repolarization period to the nerve's resting potential . it's the time taken for recovery of a neuron to generate another impulse being excited by another stimulus . so if nerve doesn't have refractory period they wouldn't be able to return to its resting potential &amp; generate new impulse . moreover the repolarization potential further exceeds its value and cause hyperpolarization , so its badly necessary to restore to resting potential by expelling na+ and taking k+ in . unless it would be impossible to restore the resting potential &amp; be ready to get excited to transmit another impulse via the electrochemical pathway . one more benefit of refractory period is that it causes unidirectional impulse conduction.
I didn't get the 2nd part of your question. What are you trying to mean , make it more clear.