When you have an attachment to an outcome, you are trying to create from old energies – from your limited self, that will judge things as good or bad based on how close they present to how you think they should look. If they do not, you experience disappointment. It is an exercise of control.
When you stay open and accepting, you are co-creating from higher energies, allowing the universe to deliver what is absolutely perfect for you, in all ways, when the timing is ideal. It is a demonstration of faith and trust, a knowingness that there is divine wisdom working along with your soul, to create for the highest good of all. It is an exercise of surrender.
The first is trying to create from a very limited vantage point, that is very constrained and resistant to expansion. The second leaves room for miracles. Which would you prefer? ~Archangel Gabriel