A marketing dashboard is one of those things that sounds like it should take weeks, a fancy BI tool, and a data engineer to set up. In reality, a simple dashboard can be built in an afternoon—and it can completely change how you plan campaigns, explain results, and decide what to do next. The trick is keeping it simple on purpose: a small set of metrics that connect to real business goals, a layout that makes patterns obvious, and a routine for reviewing it so it doesn’t become “that spreadsheet…