Sean is considered the worst in SF3, but good players are able to use him effectively.
Just don't tell Phil that. You'd think he'd at least try to use Q more and spam his taunt which boosts his defence, but I guess that's for scrubs.
Okay, explaining tiers and good characters for you scrubs. First off tiers don't matter when there is a gap in skill level. A good tier list should be a measure of their match ups against the rest of the cast. Like for example a top tier character against two equally skilled players should have like a 60-40 (60 wins out of 100) match up against any character that you throw them at. Or possibly just like very few unfavorable match ups (winning less then 50 out of 100). It depends on how well the game is balanced and how the tier list is made. Get the idea?
Now what makes a character good or bad? Or rather, what makes the match ups good or bad. Tools. What a character can do. Especially in comparison to other characters. That being important because like someone with really damaging fireballs, but slow, would be ass in Third Strike because parries can repel fireballs. As a really broad example. Please do not start an argument on that. Now these tools can be really subtle, like start up frames or the ability to combo. Which is where Sean kind of falls in Third Strike. His numbers are just terrible essentially.
So where does this leave Phil actually? Phil is a bit of a skill gate player. Because he plays skill gate characters, pardon my TVTropes name for it but I like the name. It means that he plays characters that are hard to beat if you are a noob, but easy to beat if you're remotely good. These take the forms of characters with really damaging buttons. For example a better character in a fighting game will have huge combo output and or all kinds of stuff they can do. But Phil plays like Zangief, who has very little tools, but each of his moves does huge damage. So, its kind of like slopping in pool/billiards. Phil's whole strategy has always been catch in easy, giant chunks of damage, where you can get it. Credit where it's due, that can be hard as in SF2 damage was kind of proportional to how hard it was to perform the move. Like Zangief's 360 does giant fucking damage, because it's really hard to set up and physically do. Because Capcom didn't initially realize people would just perfect these inputs. But taking away credit because that's how Phil has
always played. That's by and large his secret EVO win. Huge damaging characters, exploiting areas that are hard to defend. Means his opponent can make fewer mistakes than he can. And because this is a game no one knew, it was just everyone making mistakes.
Pretty much, Dan was originally a meme character Capcom added as a shot at SNKs Art of Fighting (wears a Ryo gi, long hair like Robert and in pink like Yuri) his fireball is shit because that's how the AoF mechanics works you had a ki meter the lower it was the weaker the move.
While my autism is on full blown mode. It was also because Capcom viewed Art of Fighting as SNK just stealing their game. How cute the joke was is up in the air as the AoF people were former Capcom guys. So it could be a bitter "ha you guys made an inferior product". Or a ribbing sort of "Look at this cute SNK nod we made, but he sucks because our old coworkers are just the worst, winky face"