Here's a common beginner mistake that has nothing to do with skill: planting the right seed at the wrong time. A seed packet's instructions are usually written for a national audience, which means "plant in spring" can mean March in Arizona and late May in Minnesota. Follow the packet literally in the wrong climate, and you're set up to fail before you've even opened the packet.
That's what USDA hardiness zones are for -- a rough map of how cold your area gets in winter, which in turn tells you when it's safe to plant without frost killing a young seedling. You don't need to memorize the zone system to use it. You just need to know roughly which region you're in and let that drive timing.
That's exactly what our Zone Quiz on the homepage does -- enter your ZIP code and we'll tell you which shipping group you're in and roughly when your box's contents are meant to go in the ground. It's a coarse match, not a precise one (a full house-by-house microclimate model is overkill for a monthly seed box), but it solves the single biggest cause of beginner planting failures: timing.