Mr Inspector, a qualified building inspector in Melbourne, took the above photograph during a building inspection he carried out in Hampton East which shows a cracked roof tile.  Cracked roof tiles are commonly seen during Mr Inspectors Home Inspections due to age, trades person walking on same and the like.  Hail damage is also a cause of many cracks in tiles.

Technically this is considered a major defect as further deterioration (leaking into the roof and ceiling) may occur if it is not replaced.  Replacing a roof tile takes about 20 seconds so in the scheme of things it is an easy fix, but one that must be replaced as soon as possible.

This actual house inspection in Hampton East did not show any evidence of staining on the bedroom ceiling directly under this cracked tile but the thermal imaging camera picked up the dampness.

This would not be seen by a potential buyer during an open for inspection and the reason why you should get a qualified and experienced building inspector with the knowledge and advanced tools to carry out a thorough inspection before you buy.