Four surfaces are in common use, and they are not interchangeable. The same shot arrives at a different height, at a different speed, at a different moment — which is why players who are strong on one surface are sometimes ordinary on another.
Clay is the slowest. The ball bites into the surface and sits up higher, points run longer, and the court gives enough that players slide into shots rather than stopping dead. Patience wins more here than power does. It is also the surface that needs the most upkeep — watering, brushing, lines swept.
Hard courts are the middle ground and the most common, in Bangkok and nearly everywhere else. The bounce is true and predictable, the pace is medium, and the surface does not give — everything that leaves the racquet arrives roughly as it was sent, which makes it the fairest place to learn what your own shots actually do.
Grass is fast and the bounce stays low, so a serve does more and a rally does less. It is rare, seasonal and demanding to maintain. Indoor carpet and other synthetic surfaces sit near grass for speed but without the weather or the irregularity — quick, consistent, and unaffected by the afternoon.
General guidance, not a research finding.