Why are narcissists insecure?

They are super sensitive to criticism and go to great lengths to protect their ego to maintain their sense of superiority. They may also rely on external validation and approval to feel good about themselves.

What makes you think they are a narcissist?

Because narcissists know, deep down, they are living a lie. They have to act great to make themselves feel better about themselves, but they know they really aren’t great. They’d rather drag others down rather than work to lift themselves up.

It depends on the person’s specific patterns, but what @seawulf575 said tends to broadly describe many of them (and some others).

Narcissists are individuals who are characterized by grandiosity, a need for admiration, and a lack of empathy. They exhibit these behaviors not necessarily because of a lack of self-esteem or insecurity, but because they believe they are entitled to special treatment and admiration. They may have an inflated sense of self-importance and believe they are superior to others, and their behaviors are an attempt to assert their dominance and control over those around them.

They prefer to get energy from others.

Relying on others for energy is not stable, and involves spending more energy controlling the supply. Which in turn means trying to control others, to keep a steady supply of energy.

I think they lack an inner sense of worth and must rely on external validation which must be fought for constantly.

I worked with a narcissist in the past for about 14 months. He was constantly lying, and always with the underlying purpose of making himself look good. He had no empathy, as somebody above mentioned, but rather he was only interested in promoting himself. If you think his actions make no sense, it’s no doubt because you and your coworkers have a normal amount of empathy like most of us do, and which case his behavior is going to seem unfathomable. Those of us who are not narcissistic are often horrified at how somebody could act that way because it goes so against what we believe we as humans should be like.

Are all narcissists insecure? Can you be insecure and not be a narcissist?

I work with someone who seems to have narcissistic tendencies, at the very least. When I noticed it recently, I asked if they would like to consider our other coworkers’ preferences, but they assumed that our coworkers were fine and continued to stay in their bubble instead of checking in. They often try to choose my lunch break time so we could take it together, instead of asking if I have plans for it first. They are constantly posting and reposting selfies on social media and talking about how attractive they are, it seems as a way to build themselves up because they don’t take criticism well.
They once told me that some old friends called them out on it before, but because they couldn’t take the criticism of being called a narcissist, they cut those people out of their life completely, telling me that they were shit. I understand, as I can be insecure sometimes too, and maybe their friends said it in a hurtful way. Maybe they were just shitty friends, outside of that comment. But yeah, I would say this person in particular is quite insecure as well as another narcissist I know from years ago. I can’t say this applies to everyone though.

Unless they’re actually diagnosed as a narcissist, can we try not to throw that term around so much? Not every asshole is a narcissist. Sometimes they’re just an asshole.