A process, not a permanent change — and one that varies a great deal from one head of hair to the next.
Smoothing and keratin treatments get talked about as if they are a single, predictable thing. In practice the process, and how hair responds to it, varies enough that what worked for someone else's hair is not a reliable guide to what will happen with yours.
The treatment is applied to clean hair, processed under heat, and finished according to the particular system a stylist uses. The broad steps are similar across methods; how the hair actually takes the treatment depends on curl pattern, density, and prior chemical processing.
Results fade as treated hair grows out and gets cut over time, on no fixed schedule. That is simply how the treatment works, not a sign it was done incorrectly, and it is worth planning for rather than being surprised by later.
The same treatment can behave very differently depending on natural texture and how much processing the hair has already been through. A stylist should be honest that your results may not match a photo of someone else's hair.
Smoothing and color interact, and the order and spacing between the two matters for how both hold up. This is worth raising directly if you also color your hair, rather than booking each service separately without coordinating them.
Low humidity and hard water are part of daily conditions along the Wasatch Front, and both affect how treated hair behaves and how long it holds between services. It is a reasonable thing to ask a stylist about directly.
Ask what the process involves for your specific hair type, how it may interact with any color you already have, and roughly how long results tend to hold given how your hair behaves. A stylist without a real answer to any of those is worth a second opinion.
Tell us your hair's history and get matched with a stylist who works from it, not around it.
Get Matched With a StylistA quick description of your hair now and what you want is enough to start.