Oh I don't know...
BECAUSE THEY ARE DIRECT PREQUELS. It's not about the plot, that's only part of the mess. I can't do it any better than red letter media and if I try to repeat it all here I'm just going to typing a lot.
Go do yourself a favor and watch the red letter media clips. It pretty much covers every angle. Nothing in the prequels makes any damn sense when paired against the original movies.
You don't need to have seen either trilogy to understand or watch the other. There is no reason to compare them.
And I have watched all the Plinkett reviews for the prequels and they're funny as hell, but alot of his complaints stem from comparing the two trilogies.
Please describe Mace Windu to me. Go ahead, describe him. And I'm not talking about the robes or his skin.
Bad a s s mutha fuc ka.
I'll do one better and describe all the other major characters too.
Padme - brave, devoted, and curious
Qui-Gonn Jinn - defiant, rogueish, and dashing
Obi-Wan - disciplined, reliable, and honorable
Anakin - whiny, avaricious, and brilliant
Palpatine - genius, powerful, and manipulative
Yoda - stoic, stern, and erudite
Just because the 4 idiots Plinkett interviews couldn't describe any of the characters, doesn't mean nobody else can.