Discipline without motivation: yes you can

Motivation helps, but it cannot be the primary engine of your life. If you only do what is important when you feel like it, you will end up erratic. Discipline shapes character because it teaches you to act according to what matters, not just according to what you feel. That is where interior freedom grows. The will is strengthened like any habit: repeating good choices when they are hard. Small victories prepare you for decisions of greater weight.