You have gotten bad advice in your life. So have I.
You have also given bad advice. So have I.
Advice is a strange thing; it is contextual.
For example, if you give me advice about something that I don't know, but you do, that might be good advice, assuming I take it, apply it to my life, and enjoy a benefit from it. But if you give that same "good" advice to someone else, someone who knows even more about the subject than you, that same advice might be "bad" or outdated (you just are not aware that it is).
It's interesting to think about why bad advice is given. I have identified three possibilities:
1. The advice giver is ignorant, and simply 'believes' he is giving you accurate guidance (but is not).
2. The advice giver is malicious, and is intentionally wanting to point you in the wrong direction.
3. The advice giver's information is outdated.
“When experts are wrong, it’s often because they’re experts on an earlier version
of the world.” (Paul Graham)
Focusing on the third reason, I believe this is why we are seeing more and more distance between traditional academics and anyone who lives outside of the academic world.
It's been observed that we have 21st century learners being taught by 20th century teachers in 19th century classrooms. If that doesn't say outdated, I'm not sure what does. Universities are cluttered with tenured professors who have not experienced the "real world" in years, yet are teaching the new generations to go out into that world...a world that looks very different than it does in a classroom or textbook.
I am strongly of the opinion that those who teach, advise, coach, lead or manage must keep learning or risk becoming outdated. Outdated becomes obsolete quickly these days.
I do believe that most people are not trying to be wrong or outdated, but they are if they have stopped learning and growing while things keep changing.
“In times of change, learners inherit the earth, while the learned find themselves beautifully equipped to deal with a world that no longer exists.” (Eric Hoffer)
While some things are simply foundational or constant, most things are constantly evolving as we get new information, new perspectives, and new inventions that allow us to do more, think more effectively, and make things more efficient.
Learning from the past...and then leaving it there...is key. That is why John Dewey once said, "If we teach today as we taught yesterday, we rob our children of tomorrow."
Bad advice is common. It's not always due to ignorance; sometimes, it's due to people who stop learning. Make sure you don't become one of them...they become obsolete quickly these days.