Being present on only one social network in the modern world is almost as inefficient as not being present on any one.
Synchronization between all social networks of the same brand leads to the creation of an eco-system, where each social network complements the other. For example, you can post a video on YouTube, a backstage or teaser of this video on Instagram, and post a description of the process with interesting events, difficulties, and shooting estimates for this video in Telegram.
Creating an eco-system allows you to tell consumers even more about your brand, and allows them to immerse themselves in a new world with values and ideals that they share. In other words, by syncing social networks, we create a community of "our own" people who will be brand followers and become "walking" advertising by themselves.
To better understand how such an eco-system of several social networks works, we can cite the following fantasy as an example. Imagine a large hall in a museum with high ceilings and columns. In the very center of the hall, the main exhibit is the ideology and position of your brand, but you can not enter this museum, and you can only look at this exhibit through the cameras that are installed in this room. Each camera is a specific social network: FB, Instagram, YouTube, VK, Telegram, LinkedIn, and so on. So, if you run only 1 social network, and even that one with interruptions, then your potential client will be able to look at your brand from only one angle and then in a cut-down format, as if the camera sometimes turns off and does not show anything. If you run multiple social networks, having thought out the overall strategy of your brand's presence in social networks in advance, then the picture in your client's head about your brand will be much wider and the chance that they will subscribe/make a purchase/repost or just think positively about you (the brand's power in its ability to influence consciousness) greatly increases.
Bill Gates once said: “If your business is not on the internet, then your business will be out of business!”
It was the year 2000. Now it would be appropriate to paraphrase the phrase like this: "If your business is not in social networks, then you are not in business!"