This has been posted at least a dozen times.
The wind speed is constant for the round, strong is that way for all 9 or 18 holes as are the other wind speeds selected a the start of the round. However in WGT land there is no continuation from hole to hole in terms of direction. Each hole is a world to itself and the wind direction is random. So even courses like St Andrews and Kiawah which run in the same direction for almost half the holes can have a wind behind you on 10 at Kiawah and directly in your face on 11. Same at St Andrews, a wind behind you on 4 can be into you on 5.
I'm not saying this is how it should be but rather this is how WGT has chosen that it be.