Thermal cycling is used for accelerated wear testing in industrial engineering. There is equipment that has best reliability if run 24/7 and kept at a steady temperature. So there is a grain of truth to what is being said.Where are you guys getting this information? Can anyone please post a link to any references or scientific proof to support the above statements?
Anyone here keep their car engine running 24/7 in order to avoid wear and tear from starting and stopping the motor?
You can Goggle around about “thermal cycling”. Here is a NASA paper how it is used for accelerated wear testing - https://nepp.nasa.gov/DocUploads/99810235-C28A-4A8D-BD52223A33EF7CDF/ASME-Hawaii993-lockeed.pdf
There is a tradeoff with a pump motor between the stresses on its windings and electronics due to thermal stress versus wear on rotational parts like bearings and seals that wear if let to run 24/7. Starting capacitor failures and winding burnouts are likely accelerated by thermal stress. However bearing failures are caused by total run time.
I am just answering your question and not advocating for or against running 24/7 will improve reliability.