My experience is that the only thing that actually works is making the plan simpler. As in: implement the simplest version of whatever you're building at the sa

My experience is that the only thing that actually works is making the plan simpler. As in: implement the simplest version of whatever you're building at the same time being mindful that you'll have to eventually include all the features. With such a solution: -You can start dogfooding early on. -There's less to go wrong. -There's less sunk cost in those of the features that don't make it to the final product. Integrate one of all those payment processors that were required, one external API and move on. Also don't do fancy, handcrafted components on the frontend. Or component libraries for that matter. Have separate tickets for validation. Once you're finished with that you'll find that in the meantime the Nth payment processor went bankrupt, Nth external API was deprecated and UX finally managed to convince the stakeholders that a color picker the shape of a peacock following the mouse with its gaze is not the best solution in terms of user experience.