A turntable also inhibits superheating of water. A superheated cup of water will expand to steam immediately if disturbed before it cools: https://www.snopes

A turntable also inhibits superheating of water. A superheated cup of water will expand to steam immediately if disturbed before it cools: https://www.snopes.com/fact-check/boil-on-troubled-waters/ https://www.snopes.com/fact-check/boil-on-troubled-waters/ The turntable's motion ensures the water is somewhat "disturbed" and minimizes superheating.