A short visit can carry a long memory when the attention is undivided.

Length is a poor measure of what a visit gives someone. Twenty minutes with your phone face down and your questions genuine can land harder than an afternoon spent half elsewhere. What people keep is the sense of having been fully met, and that has little to do with the clock. Divided attention is felt even when it is perfectly polite.

If you have been putting off seeing someone because you cannot spare a whole day, offer the half hour you do have. Leave the phone in your coat. Ask a second question after the first answer, and let the visit end while it is still warm.