You are an adult. You screw up I'm not gonna be fluffy about your lack of ability or aptitude.
Asked you to do a job knob. Qualified and competent? Then tell me why you didn't do it.
Don't mind me if I think you are an idiot for not doing your job. You work for me and suck it up princes
I'm not mean I tell you that you sucked at that task. You took the job so do it!
You may get away with this in the corporate world where there are dozens of people employed and everyone has a boss above them.
If you run a business and you treat your employees as such, you will have a very high turnover in staff.
You can get your point across without being condescending or belittling anyone. You can ask the same set of questions in a different tone and it will yield better results and keep the culture positive.
If this is how you really feel, you are not a leader. If you're in charge, you're allowed to think that someone is incompetent/"idiot" but you're never supposed to say it. Ever. Your job is to help make their job easier, ask them questions, find out what went wrong and provide a real solution to the problem. Pointing the finger and being passive-aggressive will never work long term.