Is it necessary to explain why you ending claim?

After the initial exuberance of the imminent end of ESA (CB) with news that NI contributions would continue to be paid doubts are creeping in.
Just how much per week is a single persons paid NI contribution please?
With the prospect of no other income or benefits coming in it doesn't seem like much of a life.
Im now thinking it might be better to have done with the claim all together.
There are many ways to close the lcw claim all together,there might be slight improvement in ones condition enabling one to seek work,but if you totally close the claim is it necessary to explain all this in detail once again as an improvement of circumstance?Seems a bit pointless if the object is to finally close the claim?
Theres always the question "What are you going to live on?"
Even if you struggle through by auctioning possessions etc.The ATOS Doctors are bound to perhaps ask that?
So can just say to The DWP "Close my claim"with no further form filling or explanation please?

Hi Gordon,Just re:NI Credits yes I understand they are credit stored up for ones pension in years to come.
Assuming a pension is very roughly £100 p.w. just out of interest what percentage of that roughly do they pay in on your behalf weekly?
Only very approximate amounts as obviously by 2025 whatever the amount might be very different!

James, it does not work quite like that. For each year you are on ESA, you get a 'tick' made against that year to say that you have had NI credits awarded, no money is actually exchanged. You currently need 30 years worth of credits or contributions to get full state pension.