How to work hard without time pressures?Watch
When instead all you're doing is working to other peoples' prescribed schedules and demands, naturally, when their pressure isn't looming over you, you won't feel motivated.
Whereas if your goals are your own, you're reminded of it every day you wake up and have to live with yourself, and will feel the pressure every day.
If you're smart... you can find a way to combine both of these effects into one and really take off the start line. Or burn out instead, if you're not careful and don't pace yourself (like me).