For most people, the stakes simply aren't high enough.
There's not enough reason to get up early and work, get off Facebook or get into shape.
Put most simply, most people don't have a compelling enough why. If they did, their whole life would be different. Life, apparently, isn't worth giving everything they've got.
Most people don't want to assume greater responsibility, and thus, greater freedom. Responsibility is not something outside of you, nor is "security" outside of you, like in a paycheck.
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These things are internal. And the more responsibility and security you choose to have, the more you are enabled to be then do and then have.
When you chose greater responsibility over your life and the welfare of others, you can't help but be compelled to live at a higher standard. You have a reason, no, a responsibility to be and do your very best in everything you do.
Such a sense of responsibility provides more than enough motivation and urgency to push through exhaustion and sometimes despair. Indeed, your why will empower you to endure any how, as Frankl explained.