Is the first impression the one that counts?

I have never been able to understand those who voted for a party at the age of 20 and today, at the age of 80 (60 years later), continues to have the same political ideology as before, despite that everything has changed.
But don’t misunderstand me. I do not want to speak about politics, nor declare my position.
I started with this example, but the point I am making is more widespread. I would like to try to understand, together with you, how important first impressions are.

My opinion is that

a same thing, whatever it may be (an opinion, an idea, a project and so forth) should always be viewed from different perspectives so it can be questioned if necessary.

And this, by no coincidence, is also one of the obligations of those who, like me, work as a mechanical designer. Think of the number 6 written on a sheet of paper placed on a table (classic example that we technicians love). The person sitting on one side of that table sees a 6, but the person sitting on the opposite side? He will see a 9 and he will be just as right.

If we think about it, in fact, learning to look at something from different perspectives leads to new thoughts and points of view that maybe we hadn’t considered before and that, sometimes, may even completely change the opinions we previously had (whether good or bad).

So, as far as I am concerned, the first impression is not always the one that counts, but only if we are talking about an opinion.
In fact the question of the impression a person makes during one’s first meeting is something quite different.

In my personal experience, the first five minutes of a discussion are fundamental to get a fairly clear idea of the person sitting before us and whom we had never met before. Five minutes, no longer. Especially when it is a negative impression.
Do you think this is too extreme? Perhaps so. But I assure you that my experience in life and at work has led me to become, on the one hand more intolerant towards unfair behaviour, but – on the other hand – to take a more reflective approach and pay attention to smaller and more indicative aspects. Aspects which, when grouped together, contribute to creating a very precise image of a person.

Though I am never swayed simply by form, or an image in itself. Obviously there must be a minimum of logical sense, but there are other aspects that I look for in a person.
If, for example, I have to interview someone for the position of sales manager and the person in front of me looks shabby and dresses badly… well, it is difficult for me to imagine this person will represent my company and its image well. From a logical point of view.
But more generally speaking

I don’t usually base my opinions on appearance.
What I do pay attention to is what a person says and how he says it. And it is this aspect that normally contributes to creating an accurate profile, from the very first minutes of conversation.