Never leave your back undefended. Basic rule of combat.

Of course this means you can easily back yourself into a corner. Figuratively, if not also literally.

This is why it's better to have your back protected by something that can both (a) keep you safe and (b) get easily trampled under your feet if you have to turn tail and run.

And thus: thieves were invented.

Transcript

Obi-Wan: We're being slaughtered here. There are too many attackers. We need to coordinate.
[SFX]: Pow!
[SFX]: Whooom!
Padmé: I had a plan—
[SFX]: Pow!
Obi-Wan: Our laser swords can deflect everything from the direction we're facing. Let's form a tight circle.
[SFX]: Whooom!
Anakin: That sounds workable. Padmé, stay behind me.
Obi-Wan: Okay, now we just need to hold this until—
Nute Gunray: Cease fire.
Obi-Wan: Giving up, Nute?
Mace Windu: {aside} I gave in to my anger. That's the Dark Side.
Nute Gunray: On the contlary. You have made a clucial tactical error.
Nute Gunray: If my dloids fire, your defrections will destloy them. But as soon as you break formation, you die.
Padmé: A stalemate! We'll see who blinks first.
Obi-Wan: Yes... Us, or the robots that don't eat or sleep.
Padmé: Yeah! We...
Padmé: Hmm.
Mace Windu: {aside} I'll never kill again.
[SFX]: < squee bzzt doop pop po-bak-jang >