Clarity is very important here. You need to be very clear on outcomes, expectations, measures, and consequences. Then when something doesn’t happen as it should, you have a nonpersonal way of showing it and discussing the gap. If you didn’t complete the step of setting expectations clearly and you can have only a vague conversation to the effect that the result is not good enough, it too easily becomes a personal judgment. Clarity of expectations builds trust in itself because people know what to expect and what they will be measured and judged on.