Conditioning is an ESSENTIAL part of every hair routine, but for wavy, curly and coily girls, it is even more important. However, every time you condition your hair, you leave behind residue which doesn't rinse away fully. Over time, this accumulation can be a problem, especially for people with for fine hair, which is a common wavy girl issue.
Hair build-up from conditioners can make your curls look dull and cause flyaways, limp waves and even grease due to cationic detergents in conditioners.
If you try to wash away a cationic detergent (conditioner) with an anionic detergent (shampoo), a charge interaction occurs between the two, leaving you with hair build-up from both. Low pH shampoo deposits even more anionic surfactant, so this is not the solution.
Short-chain surfactants like alkyl sulfate, alkyl sulfonates (sodium deceth sulfate) are better at removing this residue than standard sodium or ammonium lauryl/laureth sulfate shampoos. These are often regarded as being harsh on hair, but more effective at removing hair build-up without adding as much to the problem.
If you shampoo regularly (not all wavies do!), then be sure to include a clarifying shampoo in your routine at least once a month. If you're still experiencing hair build-up, which you will see as grease, limp waves or frizz, then up your clarifying routine to once a week.
Keep in mind that clarifying shampoos will strip your hair and scalp of all essential oils while also removing the build-up. This means that your waves will be a bit dried out. By following up with a good conditioner, leave-in and an essential oil (rose oil is best for waves), however, you won't even notice the clarifying effects, other than less frizz, more volume and increased shine!