Check focus before the second frame
A simple routine for separating a focus error from camera or subject movement.
Look at a fixed edge
Find a roofline or window frame in the photograph and magnify it. A fixed object gives you a better check than a person walking through the scene. If the edge is soft, inspect your focus and tripod setup before changing exposure.
Change one thing
Make a second photograph using the timer. If it improves, the shutter press may have moved the camera. If it remains soft, use magnified live view to check focus and make another frame. Keep the camera and composition in place while comparing.
Wind, condensation, and a moving subject can all affect sharpness. Treat them as separate questions. A sequence of deliberate checks is faster than changing every setting and wondering which change helped.