As far as I know, there may be a number of factors why the Mi 13 is discontinued.
First of all, with the continuous development of technology, the market demand for mobile phones is also constantly changing. As an old phone, the Mi 13 May not be able to meet consumer demand for new features and better performance.
Second, the company may decide to put its resources and focus on launching more advanced phone models to stay competitive.
Finally, the market competition is fierce, and other mobile phone brands have launched more attractive products, which may lead to poor sales of the Mi 13, and thus the decision to stop production. In short, the shutdown may be to adapt to market demand and remain competitive.