Sometimes you won’t want to apply scale or rotation if you want unqiue effects. Using an empy with an array is a good example or when using constraints is another.
When you are starting out I would say it is “The SAFE thing to do”
These helped me until I was more comfortable knowing what tools did more comfortably:
1. model with your object’s origin at the world origin with the line of symmetry dissecting the world origin
2 model with Rotation and Scale set to 1 (or applied to 1) when using modifiers that you are still learning about
3 break these rules at any time when messing around or learn what they do and test what behavior they provide. Sometimes you just gotta be a Mad Scientist to learn this stuff better.
