There are three ways of loading relationships in Laravel. Tim MacDonald, a freelance dev based in Sydney, explains them all.

It is often useful to show the number of related models a given instance has, but not actually need any specific information about the related models, just how many exist. In this scenario you do not want to load all of the related models into memory to count them, we want our database to do the heavy lifting for us. Laravel offers a number of ways to retrieve relationship counts.

https://timacdonald.me/loading-eloquent-relationship-counts/