Use words people recognize
An interface is a conversation. Labels should describe the action people expect, and messages should explain what happened in plain language. When an action needs attention, show the next useful step.
People should spend their attention on their work, not on decoding the interface.
Show the state of things
People need to know whether an action is waiting, complete, or unsuccessful. Clear status messages and visible progress reduce guesswork. A disabled control should have a reason; a submitted form should have an honest outcome.
Leave room for attention
Visual hierarchy helps people decide what matters. Space, contrast, and consistent patterns can give a busy task a calmer shape. Accessibility belongs in these decisions from the start, including keyboard access, readable text, and motion preferences.