1. Excessive film thickness. Failure to allow an ample flash time in previous coats.
2. Using the Thinner which evaporates too fast
1. Allow sufficient dry time before using the vehicle
2. Wipe the paint film clean. Do not allow trickles to remain on paint film for long especially while the surface is hot (or under the sunlight).
1. For few water marks, sand with removal agent.
2. In extreme cases, scrape the surface and refinish