The product does not work. Imagine washing your hair just with a conditioner -- how will it look? Heavy, flat, dull, that's what you get.
To remove dirt from your hair you need a product that breaks out grease, something like soap. Shampoo is soap for your hair. Conditioner is a softener. Think about washing your dirty clothes. I think washing your hair works on the same principle. First, you need to clean, the to soothe. But Wen does neither of these.
My advise - invest in a good, proven salon hair product. Something like REDKEN.
Or, if it is costly to you, use Pantene and such.
Product or Service Mentioned: Wen Conditioner.