The advantage of using an oven cleaning service is that the specialist ensures that chemicals for the internal cleaning of the oven are thoroughly cleaned.
Trained cleaners often have all the cleaning equipment that is needed. Specialists, for example, must remove all the linings, shelves and trays for decarbonization from inside the oven.
If these chemicals are not removed, the next time you use the oven, these chemicals will evaporate and then the food inside the oven will be destroyed.
One of the major advantages of hiring a cleaning company is a dry oven. There will most definitely be a lot of food waste in the walls of the oven when the oven has long been not cleaned.