A student of my Mastering Audio in Logic Pro X Course asked me a few questions about loudness. I thought I would share with you some points that I made.
The right loudness is material dependent.
Music is a dynamic art form. It doesn't have one loudness, it's dynamic by nature.
Loudness management is everywhere. It's on all major platforms and even Soundcloud said it's "on the list". But even before that, managing the output volume on playback is part of the experience of listening. It's ingrained in us. Listeners do it without thinking, whilst us audio people endlessly debate and theorise.
If you pursue maximum loudness you are trading longevity for short term gain. It may seem loud at first, but if you want people to listen to your song more than once, they will quite quickly find it fatiguing to listen to, even if it's normalised.
When you find the loudness sweet spot (which takes a lot of practice) the music will always come out at it's right loudness. For any song, that will be louder than some stuff, and quieter than others. There is no industry standard and no such thing as 'radio ready'. For your master to be radio ready, it just needs to be mastered well. Radio stations actually apply processing on their end anyway, so you don't have to match their loudness.
Serve the music.