Split ends occur when the protective outer layer of the hair cuticle wears away because of external stressors such as heat from irons & blow dryers and salon chemical services.
Once the internal structure of the hair is exposed (hair cuticle wears), it becomes weakened, dehydrated, and damaged, causing split ends.
Within 4 to 8 weeks when (the hair cuticle wears) a split end will start.
If the hair is not cut at that 8-week period this picture is what is happening at the bottom of the hair.
Fine hair will split in 4 to 6 weeks.
Medium hair will split in 5 to 7 weeks.
Coarse hair will split in 6 to 8 weeks.
This is why you cannot let your clients go months without a haircut. Have you ever seen someone with long hair but the ends look thin and straggly, this is because the split end fractures up the hair shaft, and part of the hair break off.
Get your clients in for their haircuts.
When a client of mine tells me they want to grow their hair, I explain that they need regular trims, but they say "I want to let it grow!" to which I explain that hair grows on average 1/2 inch a month, so if they come in at 7/8 weeks and I take off 1/4 inch, they are still gaining 3/4 of an inch. And when I say 1/4 inch I mean it!
I can give a client 5 inches of new growth in one year, full healthy hair without it looking like a rat chewed on it!!!
Olaplex is vitally important to help keep the hair tight, so make sure you use it in every chemical service. Follow that up with a good deep conditioner that has both protein + moisture + ceramides like the TRI Hair Care Keratin Amino Intense Repair.