- Is the person credible?
- Is the person honest?
- Is the person the right target audience?
Your mother will be really honest, but she loves everything you do, and is (likely) to be not credible when it comes to evaluating pitches, and probably also not the right target audience (if you are not raising from very close friends and family)
Busy venture capitalists are credible, and the right target audience, but not always honest (especially if they just turned you down). A vague compliment, your presentation is great, it is just not the right fit for us, could still mean that the presentation was a disaster. Small generic comments such as suggestions to cut the amount of slides, make better visuals, focus more time on the pain point, can create a lot of work for you completely uproot your approach to the presentation, while not necessarily true.
A geeky engineer can be honest, credible, but not the right target audience. When she thinks everything is absolutely clear, the other 99% of people might not be able to understand it at all.
In short, it is OK to ignore feedback from people. On the other hand, look out for genuine useful feedback from people who are credible, honest, and fit right into your target audience.