This is just to elaborate and re-phrase on the points from the OP:
When choosing (1) which book to read of the millions of books that there are out there to read, or (2) which advisor/mentor to go with out of the literally billions of people eager to shove their advice down your throat, or (3) even things like which diet and exercise plan to test out next to see if it works out of the millions out there... Remember that you have to say no to 99.99999% of them. You cannot test them all. You cannot give them all a shot. You cannot even give 1% a shot.
It's not enough that a book isn't the worst. It's not enough that someone's advice isn't definitely wrong.
"Might be right" is not good enough.
"Not always wrong" is not good enough.
"Isn't the worst" is not good enough.
Even being better than 99% of other books is not good enough for a book to warrant taking your very limited to read--because you don't even have time to read 1% of the books that are out there available to read.
Likewise, even being more reliable than 99% of other advisors is not good enough for you to take a person's advice.
Of all the millions and billions of applicants offering you advice or a plan that you could follow, you want to choose the advice that is the absolute #1 most reliable of all available to you.
Even one small red flag is a deal-breaker.
If the person hasn't proven their advice works by putting it into practice themselves, that is a deal-breaking red flag. It's not the only possible red flag or deal-breaker, but all it takes is one because your time is so limited and the market is so saturated.
Don't take financial advice from poor people, don't take weight loss advice from obese people, and don't take any advice at all ever from unhappy people.
Take advice from people who are already successful in ALL the ways you would want to be, the most important of which is being happy, truly happy, in the sense of having unwavering consistent free-spirited brave invincible inner peace, what some would even call nirvana or enlightenment or grace itself.
That is, unless you want to be unhappy. If you want to be unhappy, then definitely go and follow unhappy people's advice.
With love,
Eckhart Aurelius Hughes
a.k.a. Scott
My entire political philosophy summed up in one tweet.
"The mind is a wonderful servant but a terrible master."
I believe spiritual freedom (a.k.a. self-discipline) manifests as bravery, confidence, grace, honesty, love, and inner peace.