Why would a 24 volt transformer only put out 18 volts?

A 24-volt transformer outputting only 18 volts could be due to several factors, such as a load that is drawing more power than the transformer can supply, causing a voltage drop. Additionally, if the transformer is not fully loaded or if there are issues with the connections or wiring, it may not deliver the expected voltage. Lastly, a malfunctioning transformer or one designed for a different voltage rating could also result in a lower output voltage.