Update setup step

DEVELOPMENT.md

@@ -5,7 +5,7 @@ This is the simplest configuration for developers to start with.
 
 ### Initial Setup
 1. Run `docker-compose run --rm django pip install -e /opt/django-project[dev]`
-   1. This is necessary because the `dandiapi.egg-info` directory needs to be generated on your native machine, so that volume mounting can proceed correctly.
+   1. This is necessary because the `dandiapi.egg-info` directory needs to be generated on your native machine, so that volume mounting can proceed correctly. If that directory is ever removed, this command must be run again.
 2. Run `docker-compose run --rm django ./manage.py migrate`
 3. Run `docker-compose run --rm django ./manage.py createsuperuser`
    and follow the prompts to create your own user.