At Sepang, after losing so much time to the weather during the shakedown test ahead of the official test, Ducati boss Gigi Dall'Igna said that there was no point using Sepang as a test circuit, if the surface was not going to dry. "Maybe we have to test somewhere else," he said.
Now MotoGP is somewhere else. At Qatar, where the rain is never a concern (well, almost never), and the teams don't have to worry about the track not drying up. But arguably, the teams get even less track time at Qatar than they do at Sepang, even when it rains. The test starts at 4pm, with the fierce Arabian sun still beating down on the track. Sunset is two hours later, and it takes a while for the track to cool to the normal temperatures which will be found at the race.
Track temperatures are fine after dark, at least for a few hours. Around 10pm, an hour before the track closes, the dew starts to form. The time at which it starts tends to vary, depending on temperature and humidity, but it is very rarely before 11pm. Invisible damp patches on the track mean riders start to crash without warning. The sensible riders wait for the unlucky riders to crash, then take that as a signal to scurry back to their garages and call it a day.