In Melee, there are characters that have cheap moves that allow noobies to get a few K.O's.
First there are the moves that are cheap but are easy to counter:
(I'm not gonna post them all, just the common ones.)
-Falcos Jump A Down (Twirl)
-Captain Falcon's air kick (Jump A, Left or Right)
-Link's Spin Attack
Then there are moves that allow more trained players to keep people in combos for a longer time, which pick off and K.O noobs easy:
-Falco's Jump A Down (Twirl) then just as you land activate your reflector and repeat the A down Move)
-Falco's Grab then tap the C stick down. (Kills people at around 80% dmg.)
-Ledge gaurding (Jumping on teh ledge before your oppnonent tries to grab it)
Then there are the techniques that allow you to completely dominate any match, which your opponent is good or nooby.
-Samus's Bomb Jump
-Ice Clmibers Immobilization Glitch
-Using a strong attack such as Marth's A -> or Link's spin attack when your opponenet is coming back from the ledge .
- Suicide Kill ( Jumping off the ledge while your opponent is coming back and uses an A Down on them which usually ends up in them dying, bu if you miss you are screwed. (best if used with Falco's Twirl)
- Sheild Reflect (Pressing your sheild just as a projectile hits you, bouncing it back at them)
If you can master all of these you can not lose to anyone that dosent know these.
(I know I probably didnt get everything so dont flame)