Why is arbitrum so good?

I've been hearing a lot about Arbitrum lately, but I'm still not quite sure why it's so highly praised. Could you explain to me, in a nutshell, what makes Arbitrum stand out? Is it its scalability? Its security features? Or perhaps its compatibility with other blockchain platforms? I'm particularly interested in understanding how it compares to other layer-two solutions in the crypto space. Could you break it down for me in a way that's easy to grasp?