Tell me why. The protection of trademarks and patents is based on commercial interests. Their exclusiveness puts all competitors, that is, other manufacturers and sellers in the first place, because these competitors use my trademarks and patents and infringe on my interests.
The so-called "imitations" for personal use and not circulating in the market are beyond the protection scope of patent law and trademark law.
The most typical is the cultural market. I made a single and played it in the square. You recorded it and went home to listen. This is not infringement. But if you record it and spread it widely on the Internet, resulting in a decline in my individual sales, you will infringe. Or you record it and sell it to another person (even if 1 person makes a profit, even if 1 cent), it is also considered infringement. I can sue you for infringement in court. As for how to obtain the evidence of your profit, whether it is worthwhile or not, that is another story. What we are talking about is qualitative, and this kind of behavior is infringement.
Self-use, non-circulation, non-profit, and no harm to the interests of merchants, is not infringement.