A $100 billion dollar health care package was proposed by congressional Republicans this past summer, and afterward endorsed by some Democrats. It aims to save money by encouraging you to make big life changes. But the package will probably fail to achieve its goals for a simple reason: scarcity. Chances are you don’t have the time, money or bandwidth to follow through.

The legislation is expected to be reintroduced in the first quarter this year, and it has laudable goals. It encourages exercise by treating gym memberships as tax-deductible medical expenses. It would help cover out-of-pocket costs for high-deductible health plans by allowing people to deposit more money in tax-shielded health savings accounts. And it would permit the use of flexible spending accounts and health savings accounts to buy sports equipment.

In other words, the spending package is intended to nudge Americans to exercise more and to get a better handle on their finances. But it would require people to restructure their lives in response to modest financial incentives. The package is an active policy: It requires opting in.

Most of us won’t. We’re experiencing multiple, and often compounding, types of scarcity.

“Scarcity in one walk of life means we have less attention, ‘less mind,’ in the rest of life,” wrote Eldar Shafir and Sendhil Mullainathan, Princeton and Harvard University professors who study behavioral economics. They refer to scarcity as a “cognitive tax” that makes it hard for people to live healthy lives and make health-promoting choices.