Because if you talk about personal topics, it is very easy to involve privacy, and even touch the sensitive nerves of the other party, causing unhappiness. Emotionally intelligent people will choose to use "food topics" to break the ice.
Or, when chatting, you don't know what to continue talking about after finishing a topic, and you get stuck there awkwardly.
Many people will encounter such a phenomenon: with someone to eat together, but do not know what topic to talk about, two people sit face to face, awkward and silent to eat separately.
Emotionally intelligent people, good at observation, from a short conversation, analyze the other party's interest in the topic, and then use the other party's interest in things to pave the way for their own, in order to quickly achieve the depth of communication between the two sides.
In addition, we can also start from the current hot topics, entertainment gossip, hot current affairs, historical events, scientific frontiers.
In general, when we are talking to people we don't know very well or strangers, one of the safe ways to start a conversation without knowing their interests is to start with what they do.