This is because stories were traditionally told using the past tense. This made the narrator sound as if they were narrating events from a distance, instead of being 'present' amongst the action.

The abstract is usually in the past tense due to it showing what has already been studied. Example: “This study was conducted at the Iyarina Field School, and within the indigenous Waorani community ...

To talk about things you’ve done in the past, whether it ... going to need the perfect tense. To form the perfect tense you need two verbs. The first is often haben - to have - and you’re ...