It seems like almost everyday I see someone performing a lift/technique they have no reason to be doing. I see people performing deadlifts or squats with bands or chains when they can't even deadlift with proper form.
Bands and chains have a very important roll in certain styles of programming. They help increase strength in different phases of a lift. These variations on the main strength lifts are tools to help advanced lifters break through plateaus. These variations only become beneficial if you're already capable of lifting heavy weight. By heavy I mean if you're a 200lb male that deadlifts 700lbs and you notice that you are not explosive enough when the bar gets past your knees, then by all means put some bands on and get to work.
On the other hand if your a 130lb female with a 200lb deadlift then you just need to focus on technique and deadlift more. Same goes for the squat, bench and any other lift you're tempted to add stuff to. Sure these variations look cool but most people just need to lift heavy stuff and put it back down.
I am not saying that all you need to do are the main lifts to get stronger. Though that is true for begining lifters. Accessory movements are important in any strength program but as the name implys they are accessory lifts.
As Jim Wendler says,
Strive to have a great workout on the main lifts, and a good workout on the assistance.
Now go move better