A lookout is a bullshit position anyone can take. Example:

Captain: you need to have responsibility over your crew mates

Swordsman: you use swords as your weapon,that’s basically it

Sniper: you use ranged weapons and you can ALSO be a lookout

Navigator: your fucked in the new world if you don’t have one on your crew

Doctor: your also fucked if you don’t have one, very important position

Archaeologist: if you can’t read poneglyphs, then you can’t get the one piece

Shipwright: you fix the ship when shit happens, also very important

Cook: you can literally die from poison if you don’t have a good cook, and you can’t starve in the new world

Musician: yo have to jam when your on a ship, sometimes it gets boring(and I know y’all will be like “you don’t need one” but brook is a skeleton, that’s all I need to say)

Helmsman: you move the ship that’s about it(but jimbei can manipulate water and shit, and he saved Luffy multiple times)

Lookout: bullshit. Unless you have like a sharingan which carrot defiantly doesn’t have(or you can be a sniper and be a lookout at the same time)

You also need to have a dream(to join the SH). Yamato and carrot have the same dream tbh.

Let’s answer some questions:

Who is stronger?

Yamato>Carrot

Who is more emotionally connected(or connected) to Luffy?

Yamato(knows ace and was probably friends with him)>Carrot(A random ass bunny they found on Zou)

This is why Yamato should join instead of carrot, Don’t mind if both of them joined(probably won’t happen).