In the States, "stick to your knitting" is an idiom for focusing on an already-familiar activity. For SaaS vendors, better advice was never given.
The SaaS market space is young and still evolving. As SaaS companies evolve and develop, there is a huge temptation to be all things to all customers. After all, with 40 percent growth rates across the board, isn't it tempting for a SaaS HCM vendor to grab more revenue with a new financials suite? Yeah, unless you're an Oracle or a Salesforce or an IBM...don't do it.
The most important key to success as a SaaS provider is staying in touch with your customers: knowing their desired results and providing the best experience in achieving those results. That requires serious knowledge of business processes in a specific area of expertise, such as supply chain or project management. It's tough to build that expertise in-house. Without naming names, we've all seen recent examples of successful SaaS vendors branching into new product areas only to get their heads handed to them on a platter.
The alternative? Partner with other SaaS providers offering complimentary expertise. Don't build up that new HCM Suite if your strength is in Sales software...team up with somebody already dominant in that market space. If you focus on project management, find a partner with a solid financials offering. Build win-win relationships that benefit you, your partner and your customers. Doing so keeps you nimble, responsive, and best-in-class.
Stick to your knitting. Your customers will love you for it.