It moreso depends on the type of hair you have. I have fine, 4 textured, relaxed hair. Its super important that I follow up even a light protein treatment with a moisturizing conditioner. It took me almost 8 months of breakage, frustration, and setbacks when I first started out before I finally figured it out. I think 3 textured relaxed hair reacts differently.
For example...If I go light with the protein, say Aphogee 2 Minute, then I go light with the moisture right afterward. In that scenario I'm talking just a few minutes of each while washing my hair in the shower.
If I go hard with the protein, like Aphogee 2 Step, then I follow with a more intense moisture DC. Mizani Intense Moisturizing treatment is a good one, and in this scenario I go under the dryer for both steps.