How to play MP4 format on Mac?

Maybe some of you have encountered the following problem and can suggest a solution. I am using a Mac laptop. It is great for work. And for watching a quick video on YouTube it's fine too. But when it comes to videos in MP4 format, my player quite often has playback errors. I don't fully understand what this malfunction of playback of this particular video format is connected with. I understand exactly what prevents me from enjoying watching content in the most common MP4 format on Mac. So if you have found a solution to this problem, please share.

Hi. I was just thinking about the problem of not playing MP4 on Mac. Like, what is the reason that on different operating systems it is easily played, and only on Mac it can not work properly. And why those who work on creating players, do not solve this issue. It would increase the number of users of their players. In general, somehow it is not clear.