When running a startup, you are making an INSANE number of decisions day in and day out. The source of most of these decisions is your experience. Experience failing, experience succeeding, experience reading about others in similar situations. You associate the x decision with y result because you come across it beyond a certain threshold. 

There are times where I literally make a judgement on my idea or another person's idea...and STOP myself to think for a minute or two. Problem is, if I did that about most decisions, I'd spend all day busy running analysis. If I don't do this, I fear turning into a pessimistic hag wayyyy before my time.

My most common reply when people pitch me their ideas is DON'T ASK ME! I can only be clueless. Go try it and find out for yourself! I am sure there are people with sounder judgement whose advice is worth seeking and taking. I'm not it. And 99% of folks giving out advice aren't it.

My advice is just a buncha biases formed over years of many losses and small victories. Next time I offer you advice, please consider me a fool.