"Good for a teenager" isn't much of a compliment when you think about it. It's like when I asked someone to beta read my new sci fi novel and she told me it was "pretty good for a first attempt". This is what we in the business call damning with faint praise. If I'd been publishing sci fi for over a decade and people were still saying "pretty good for someone who's never written sci fi before" I'd definitely know something was up.