Relational capital is a big fancy way of saying that having good relationships with other people is super important. Just like how you need to be friends with other kids at school to have a good time, businesses need to make friends with other people and companies to be successful.
When a company has good relationships with other companies, it can do things like get better deals on supplies, find new customers more easily, and get help when it needs it. It's like when you and your friends team up in a game—you can accomplish more together than you can alone.
So, it's really important for businesses to build strong relationships with other people and companies—this is called having good relational capital. If a company takes care of its relationships, it can help it be more successful, just like how having good friends can help you have more fun and be successful at school.