What is the Nibble Sales Strategy for closing deals?

It's big matter, if u mean the negatives of sales strategy for closing deals will said this matter not Quran or Torah, any way it's depends on the peoples who's closing with them & yr importunity of yr products or services to reach there needs or u must create the needs for them so this is one, also the nature of persons or the key person to close with, n some times u must reach his needs before closing deals with him, also we have the favoritism & nepotism most times closing and so many nibbles strategy we have especially n our countries.

Thanks fro invite - 

Agree with Mr.Ahmed Chukri answer  ! 

Nibbling is a negotiation technique in which a negotiator asks for small concessions just as a deal is about to close. This tactic takes advantage of the other side's desire to close the deal. A nibble is often phrased as "just one more thing"