I've read in the book Atomic Habits by James Clear that the solution is to only do that much time and actually just stop right afterwards, even if you want to do more. Therefore, it's at most 30 min rather than at least. This teaches you rigor and in fact motivates you more because now you know it's not actually a trick.
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The Two-Minute Rule can seem like a trick to some people. You know that the real goal is to do more than just two minutes, so it may feel like you’re trying to fool yourself. Nobody is actually aspiring to read one page or do one push-up or open their notes. And if you know it’s a mental trick, why would you fall for it?
If the Two-Minute Rule feels forced, try this: do it for two minutes and then stop. Go for a run, but you must stop after two minutes. Start meditating, but you must stop after two minutes. Study Arabic, but you must stop after two minutes. It’s not a strategy for starting, it’s the whole thing. Your habit can only last one hundred and twenty seconds.
One of my readers used this strategy to lose over one hundred pounds. In the beginning, he went to the gym each day, but he told himself he wasn’t allowed to stay for more than five minutes. He would go to the gym, exercise for five minutes, and leave as soon as his time was up. After a few weeks, he looked around and thought, “Well, I’m always coming here anyway. I might as well start staying a little longer.” A few years later, the weight was gone.
"""
""" The Two-Minute Rule can seem like a trick to some people. You know that the real goal is to do more than just two minutes, so it may feel like you’re trying to fool yourself. Nobody is actually aspiring to read one page or do one push-up or open their notes. And if you know it’s a mental trick, why would you fall for it?
If the Two-Minute Rule feels forced, try this: do it for two minutes and then stop. Go for a run, but you must stop after two minutes. Start meditating, but you must stop after two minutes. Study Arabic, but you must stop after two minutes. It’s not a strategy for starting, it’s the whole thing. Your habit can only last one hundred and twenty seconds.
One of my readers used this strategy to lose over one hundred pounds. In the beginning, he went to the gym each day, but he told himself he wasn’t allowed to stay for more than five minutes. He would go to the gym, exercise for five minutes, and leave as soon as his time was up. After a few weeks, he looked around and thought, “Well, I’m always coming here anyway. I might as well start staying a little longer.” A few years later, the weight was gone. """
From https://jamesclear.com/how-to-stop-procrastinating