Without these signals we would not be able to move or sense danger. We wouldnt be able to alter where we are going or how we are walking in order to avoid danger.
Think of the nerves like electrical wires going to a light bulb.
If the signal does not get through the electrical wire then the light bulb will not turn on. Or if an electrical wire is damaged the signal cannot get through and the light will not turn on. Or if the signal goes through the electrical wire intermittently the light bulb will flicker on and off.
It is the same with the nerves. If a nerve is damaged or trapped these signals are unable to get to the brain successfully.
The result can be Sciatica which can result in numbness or tingling or pain.