Life is just too short to keep reading a book that's not compelling or rewarding to you. But how can you know when to quit? Austin Kleon (Steal Like an Artist) recommends the Rule of 50, lifted from Nancy Pearl's book Book Lust.
Here's how Pearl describes the Rule of 50:
I live by what I call 'the rule of fifty,' which acknowledges that time is short and the world of books is immense. If you're fifty years old or younger, give every book about fifty pages before you decide to commit yourself to reading it, or give it up. If you're over fifty, which is when time gets even shorter, subtract your age from 100. The result is the number of pages you should read before deciding.
And if you're having a hard time finding time to read, check out Kleon's tips on how to make more time for books.
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