The quality of what Claude Code builds depends entirely on the quality of your instructions. Vague instructions get vague results. Specific instructions get exactly what you want.
This isn't a Claude Code limitation. It's a communication principle. Try telling a contractor "make the house nice" versus "paint the bedroom walls sage green, replace the carpet with light oak hardwood, and add recessed lighting." Same contractor, wildly different outcomes.
(My wife operates on a different principle: give her permission to "improve" anything, and she'll find something to change, tear down, or rebuild. The specificity of instructions is irrelevant. The outcome is renovation.)
Vague vs. Specific
Watch the difference:
Vague: "Make me a website."