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

What common mistake do developers make with Fillable, why does the mistake cause problems, and what is the safer approach? One recurring problem with fillable is applying it without understanding the boundary it protects. Passing the entire request object to Model::create() and relying on the database schema as the only security barrier. In addition, The fillable property explicitly lists attributes that are safe for mass assignment. 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.