You need both. You need to be planning, executing, and investing in both the short and long term.
If you only focus on the short term, you'll end up doing great things in the next six to twelve months, but be lost after year one.
If you only focus on the long term, you'll never reach the milestones and outcomes to build something that endures.
Creating a durable, enduring company requires you to do both.
Each year and each quarter you should be having discussions with fellow leaders and executives about how the investments and planning are going for both streams.
My favorite resource to help you with both is our People-first GTM Method Guide.
It's a document that helps you think through all seven aspects of how your company should be operating in both the short and long term.