When you blow a head gasket what is the most probable cause for it happening? Are the heads warped? Thanks

Probable cause for head gasket failure : overheating due to coolant leaks, stuck thermostat, plugged cooling system. Lack of service, changing coolant and flushing the cooling system
When you have a blown head gasket, it's always a good idea to get the head checked for warpage.

Thanks for the advice!