Skyler takes Walter to a storage area she has rented and shows him the giant pile of money he has made from his meth business. She then asks him “How much is enough? How big does the pile have to be?” Walter appears to have the same determination to earning revenue, but Skyler recognizes that her utility has diminished. The first thousands that Walter brought in may have excited her, but at this point it has become a hassle and it doesn’t seem like another dollar will really change her happiness level.
See more: diminishing returns, income effect, leisure, opportunity cost, scarcity, tradeoffs, utility
The Economics of Breaking Bad 