The main factors that cause flash drying are the ingredients that can be found in many hair care products. Humectants are a prime example, because while they can be great for moisturizing hair in the right settings, using them incorrectly can cause dehydration. If humectants are applied in low-humidity settings, they can actually absorb moisture from the hair instead of the air, resulting in flash drying.
Similarly, while aloe vera can be a wonderful ingredient for reducing scalp irritation (via Healthline), it also can cause the same moisture-withdrawal sensation. Other commonly-found culprits include film-forming polymers, such as PVP. When these ingredients are applied excessively and repeatedly, it can result in a buildup that leaves your hair feeling rigid, contributing to the feeling of flash drying.
Something else to avoid that causes flash drying is hard water. Hard water contains a higher concentration of metals, and when your hair absorbs this repeatedly, it makes it harder for your hair products to actually work, leading to an increased chance of flash drying.
