Most directives actually do most of their logic in a $watch(). For example ng-if will setup a watch on it's attribute, and then render/remove the dom when that changes. Watches execute during a digest cycle, so even though directives have been compiled and linked, the watch hasn't run yet to determine whether it should show the if or not.

EDIT:

You should probably think about what you are actually doing to make sure if it's what you want. Keep in mind that the ng-if is dynamic. And so at any time it might get removed or added based on whether the items array is empty or not.

This means that even if you manage to defer your dom manipulation until after the if is rendered, you run the risk of the if going away and coming back (at which point your css code will not be run again).

A much better way to do this would be to setup a watch and add your css in a watch, or better still, use ng-class and add the css in your template.