Chlorine breakdown

I have a swcg so I rarely buy jugs of bleach but wondered about a common statement made in this forum. To wit: the higher the chlorine concentration in a container, the faster it 'breaks down'. Not to be argumentative but, what is the chemical or physical process involved that would cause this to happen?
All things being equal, the age of the concentration, the storage conditions, etc., does the higher concentration really break down quicker or is this a commonly held but incorrect belief? Thanks in advance for educating me.

Larry, To my mean understanding, chlorine breakdown is a function of the initial level of chlorates in the sodium hypochlorite (NaOCl) (among other things) and that chlorate level is higher in the higher strength NaOCl solutions.

This document has the details: http://www.odysseymanufacturing.com/...nformation.doc

The other thing that impacts it is trace metals. There are always trace metals from the manufacturing process and they catylize the breakdown and have a greater impact as concentraction of the bleach increases.

Thanks for the replies & info.