Does a factory reset spoil the phone?

Factory reset does not spoil any data in the phone if the phone is already backed up by cloud storage or a phone backup system provided by the manufacturer. A factory reset is required when the phone shows some hiccups in starting and some delay in processing.

In a factory reset, the settings that were additionally installed are removed but the data, like contacts and email addresses, is not lost if some precautions are adopted before the factory reset. Important data should be stored to cloud storage beforehand so that the data can easily be retrieved after the factory reset.