Feedback from multiple sources is always more reliable than any one source. Especially when the feedback conflicts with what someone already believes to be true.
For example, if one person tells you that you have a green tail, you can confidently assume they are mistaken. If two people make the same observation, you might conclude they are in cahoots and pulling your leg. But when a dozen people insist, it may be time to embrace your tail!
Feedback from multiple sources:
The more intimately those giving feedback know and understand the person they are helping, the better. All providers of feedback must also be allowed to speak candidly, address all issues openly, and have the receiver’s best interests at heart.
When giving critical feedback, one person’s observations should always be checked against other views, especially opposing views. If two heads are better than one, as they say, even more heads are best.
Even when two people agree, feedback recipients are better off. They can feel more confident about the feedback. The more people they hear from, the better. Receiving feedback from multiple sources gives employees a richer picture of who they are, what they are doing well or not so well, and greater confidence in the majority view.
See what others say about multiple sources of feedback. Again, the more the better, as long as they are well-informed, and like I do, have your best interests at heart.