A principle of Eastern philosophy that I have come to appreciate says that a source of unhappiness is not knowing how the world works. If you do not know the nature of something or someone, you set up the wrong expectations or you attribute wrong causes or motives to others. The end result is you spend a lot of time angry or frustrated. Rocks by their nature are hard; don't expect them to make great pillows, and don't blame them for your sore neck in the morning if you do try to use one for that purpose. (Lesson learned from primitive camping.)
In my current role I do a lot of negotiating back and forth between product managers/stakeholders and development. I am reminded of a study I did back in my doctoral days as I observed the differences between these two camps during a product development cycle. I arrived at the metaphor of a couple packing to go on vacation. One is thinking of being there. That one has an extensive list of things to pack, and can change or add to the list up to the last minute. The other is thinking of getting there, and is focused on getting everything into one bag and a carry on. Every time the former makes a change, the latter sighs deeply, unpacks everything, and adds the new item, sometimes forcing a swap with something already packed. As frustrating as the latter can find the former during the packing phase, once there, all benefit from having what is needed (like sandals AND loafers AND sneakers).
Product managers are like the partner thinking of being there. That is their nature to think of all that could be useful and to keep updating the list until the last minute. Developers are like packers, focused on the constraints that each new item adds--that is their nature.
Whichever side you are on, if you can recognize the value of the other--great! If you can't, at least accept how the world works.
And be happy!