What common mistake do developers make with Helpers, why does the mistake cause problems, and what is the safer approach?

What common mistake do developers make with Helpers, why does the mistake cause problems, and what is the safer approach? One recurring problem with helpers is applying it without understanding the boundary it protects. Assuming a facade call automatically makes a method pure or side-effect free; the underlying service still performs real work. In addition, Helpers such as route, url, view and config provide concise ways to perform common framework tasks. Safer engineering approach: keep the responsibility in the correct layer, use the framework's supported API, validate and authorize inputs, avoid hidden side effects, and verify the behavior with tests.