Why must God reach the fullness of Glory (reformed theology)?

Reformed theology stresses that God created the universe for one purpose: to glorify him fully. And to reach the fullness of Glory, God must demonstrate all that would glorify him. This means that to demonstrate things like wrath and grace, there must first be misery. It's a very tidy theodicy, except it leaves me wondering why God cares about the fullness of Glory so much. The theology makes God out to be self-obsessed, and that he must prove (to whom exactly?) that he's perfect at everything. Humanity is a means to an end. The purpose of creation being for God's glory is a given, but I guess the question is why? Why is creation about that? Why must God show his full Glory, and is there even anyone to fully appreciate it in the first place? --- I want to be sure that answers focus on reformed theological positions and preferably quote known theologians and any accompanying scriptures. --- Question inspired by [this answer.](https://christianity.stackexchange.com/questions/9583/according-to-reformed-theology-how-does-the-fall-glorify-god/42495#42495)