When they say "I love you", it sounds like everything that a man could, he did.
And thats it, done, there is nothing to do anymore. It's done - I love you.
Yet, love is the process, you must "do" it. Sometimes the process is terminated (the quarrel for example), then the process is resumed. Otherwise, it looks "poor."
How it should look, perhaps a matter of taste, but with word "poor" I mean - you want to see (my personal preference) that feeling richer than you can just "do", or rather than something that has an end. As perfection for example, it is possible to construct it endlessly, and it will always only get better from it, i.e. , it should look like it is at the junction of "tangency" something. When it seems that you have touched, but the brain prompts that you're not able to actually touch it at the atomic level (as actually achieving perfection), in a word, the words "infinitely close to love" more consistent with the recognition in true love rather than "I love you".
Perfection is not achievable - it is good. Perfection / Apogee / end point / maximum of love is unreachable, it's probably also good. And every micron of movement will appear as a novelty in the relationship ... but that's another topic.