One is that while there are a lot of things that people will share with you (they often want to share their expertise/craft and be good humans), there are a number of things they won’t share with you.

Two is that when you are starting out you are in a position where almost all information from an experienced artisan is helpful. That can mean you may easily miss what they are not telling you.

This is not to say they are misleading you or hold ill will because the information they withhold from the conversation would not be useful to you anyway, as you are not in a position to use it or be a threat to them.