Can someone give me an in-depth explanation why Summoner is arguably the worst DPS?

[Leonus]

it's not meant to be easy to be top dps and dying to it is not an excuse, but ...

The good melee players dodge things, so I don't know what you guys are getting at when you say this kind of stuff. The ones that don't dodge mechanics are bad, and THINK they are good and are attempting to look good with their numbers which are more often that not still mediocre at best. This really doesn't just apply to melee dps either.

Parties just want to keep melee dps up, so tanks try to position the boss to where the melee have as much uptime as possible. Melee can and sometimes do handle all the mechanics that parties assign to rdps (which honestly isn't much in FCOB, anyone who says otherwise is a fibber) and the most you see it in is T12 with the fountain (who goes in it).

Why have a melee dps run away from the boss, into the fountain and do nothing instead of having a rdps do it that can still attack while he's in the fountain? Who can get in and out faster too because of sprint?

Can melee do it? Yea, but why? It's not the most efficient way of playing your parties strengths. Unless the tank's wanna move the boss to the fountains so the melee can keep up their chains/dot (s). Hell, me and the mnk in my static will step into the fountain if it spawns close enough to the boss and we can still attack it instead of having a rdps move since it's already right there.

Everyone that plays dps wants to be the top dps, they don't want to feel inferior. This mentality gets in the way of team play and breeds selfishness. Most people aren't willing or to make the sacrifices needed to better the team as a whole. Then you have other people who gloat about their high ass numbers and not realize that there are other people in you team that helped make that possible for you to even achieve.