Why does gladwell use the word bargain instead of agreement or deal

Bargain is used by Gladwell to set the tone of the chapter about what he is about to plead to its reader.

Explanation:

The term "bargain" is used by Gladwell as a title of chapter 9, "Marita's Bargain", of his book "Outlier:The Story of Success." Bargain, agreement and deal all means an agreement in which two or more parties are involved but in bargain something is offered with a less value, whereas agreement and deal involves equal exchange.

In his book, Gladwell speaks about the factors that contribute in "success" of higher level.

In Chapter 9, he makes his point that KIPP (Knowledge is Power Program) academy had changed its set of rules of its educational system and helped the poor students of its locality. By doing this, we will be able to create equal opportunities to those students who don't have them now. He asserts that this change requires sacrifice from our part, that is bargain.

the author develops a cold, and scared tone. making the reader shudder with fear, and suddenly become cold. i'm guessing that he's writing a scary novel, or maybe about a chilly december night.