Purugly

HP: 71
Attack: 82
Defense: 64
Special Attack: 64
Special Defense: 59
Speed: 112
So... a little fast, but that's about all this pokemon has going for it. With crappy stats and a shallow move pool, it's no surprise you don't see Purugly often in competitive play. Lets look at a few good things about Purugly. If I can find any.
Fake Out: Always a good move. This priority move gets some guaranteed damage on the first turn, usually. And if it hits, the opponent flinches. Not too bad, except it only works the first turn the pokemon is in battle.
Return: This Normal type move is always a good decision in competitive play. Good damage if the pokemon loves you to death. Oh, did I mention Purugly is a normal type pokemon? That means STAB can be added to the equation.
Sucker Punch: Another priority move. Hits if the foe if the foe tries to attack you first. Decently useful dark type move.
U-Turn: I love this move. This and Volt Switch, they both make great moves for a lead. Attack the opponent AND switch out? Hell yes. Great from running from a pokemon that will screw your lead up and get some damage off as well.
Now, some things to consider negatively about Purugly.
2x weak to fight type: Fighting type pokemon can damage this pokemon pretty bad. And keeping in mind Purugly's poor defenses, this means a baaaad outcome for the ugly cat.
Poor Attack Stat: This pokemon won't be OHKOing anytime soon, unfortunately. Such a poor stat set.
Poor move pool: Moves. This pokemon does not have many good ones. This pokemon is rather hard to play, I imagine.
So, to follow up with everything... I would advise you not to bother with Purugly. Unless you really want to...