How do I convince my (incredibly stubborn) friend that hector is a good unit?

To each his own. You can't force someone to think that said unit is great. I personally think Hector has great use. He probably just isn't very proficient in using armor units.

There's nothing you can really do to convince someone that their opinion of someone, or something, is incorrect.

Why do you bother yourself with his agreement? You know why you find Hector to be a good unit; he has his own reasons for thinking that Hector is a poor unit (I actually don't like Hector as a combatant myself and he's never scared me thanks to my Zelgius; I'll decide whether I think he's a good unit when I play him). He will have his consequences, both positive and negative, for analyzing and playing the way he does, and will you not have yours? I've seen someone build Roy to tank regnal astra on a defense tile and take no damage. Roy can be a good unit.

Contrary to what every one else already said...kick his ass in a 1v1 with a hector :)

He is allowed to have his own opinion... as long as he acknowledges that it's wrong LOL- no but srsly your friend is pretty backwards, but I know how stubborn people can be so just leave the issue as a joke lol

I can understand not like armored units as a whole -- after all, I don't like fliers myself. Has he ever tried giving these units a shot? I can't understand not liking Ike alts. Brave Ike is awesome.

I personally don't like Hector either. Compared to other green armors he just doesn't catch my fancy.

I will, however, admit that I used him TONS prior to SI and seals and such. Very useful back then.

I got a friend on a Discord channel that refuses to use even good units just because of their art, and she's quite stubborn about it. So I know the feeling.

At least some of the units she likes are good, like Fae and Soleil.

"Good" is a touch subjective. You can show him how Hector can be an "effective" unit. I still use Hector in many of my teams. If you friend has a Hector with bad IVs that can definitely make his unit struggle. Also, Hector's skills and stats tend to favor Enemy Phase bait & kill tactics, but if that's not how your friend plays he won't care how effective Hector is at that strategy. X3

But I guess, find out how your friend plays the game and see if you can make his Hector fit that strategy.

your friend has the iq of a sewer rat and should not be taken seriously