This is a question I like to ask our more developed portfolio companies who have built large markets/networks/user bases. I ask them “if you were a startup and you wanted to compete with our company, how would you go about it?”
I think it is very important to understand your weakest flanks/vulnerabilities and then shore them up. If someone will compete with you by coming at the market “mobile only” while you struggle with maintaining a large web and mobile presence, then you should know that. And it probably means you need to rethink your mobile strategy so you can close off that open flank. If someone will compete with you by offering a free version of what you charge $10,000 a month for, then maybe you need to think about a freemium offering to close off that open flank.