Usually it just the tile slide and leave opening gap if you talk about common tile roof.

I just fix mine when the one at the edge almost fell off. I just paid the guy RM80. My roof is very sloppy type. I help him to hold the ladder on the lower level roof. He found another one sliding too. To prevent future slide, I bought silicone glue to fix. The grey colored one will stay flexible for probably 20 years.

I hope I remembered it right. I read it the last time I repaired my leaking gutter.

Silicone it durable stuff. Here is my capture from an article


I just use local product sold in Mr DIY for around RM10, an x'traseal MC-201. I finished it all up during the balance after roof fixing and could not verify the claim on the product. Nothing mentioned on website though

https://www.xtraseal.com/tds/1046050993TDS%...g%20Sealant.pdf

Developers us cement because it is cheap but cement will de-laminate during heating and cooling cycle throughout the year. The roof ridges are normally cemented together. The tiles at roof field are just hooked to the roof batten which normally won't slide unless very strong wind. Many of the ridges near the edge almost fell off and I get a person that do specialize in roof work for a contractor to glue it using silicone. Usually the ridge tile that meet other ridge from different direction tend to slide off.

I'm in Penang Butter worth side. The salary for the roof guy is around RM150 per day (current).