Phenomenon
The paint film is soft to the touch, and will fingerprint or waterspot within hours/days after application.

Cause
A. Excessive film thickness.
B. Low temperature and high humidity.
C. Adding too much or little hardener to the paint.
D. Using too much retarder thinner.
E. Poor condition of the previous paint film.

Repair
A. Drying the film by heat.
B. If hardener is not added, remove the film and refinish.

Prevention
A. Using the designated thinner.
B. Follow the standard film thickness.
C. Follow the standard ratio of hardener.