The purpose of elect is the glorification of God. It's not to add glory to the already perfect God, but to reveal His glorious perfections which manifest themselves in the work of redemption to angels and men, in order that in reflecting upon them felicity may be experienced.
It's purpose is, by glorifying and praising Him, to end with all things in Him in whom all things must end, and thus to afford Him all honor and glory.
The purpose is to be glorified in His saints, and to be admired in all them that believe
This is why Election is part of the Gospel of God, the Gospel of Gods Grace !