It is common to talk of them in terms of what they tend to be rather than what they are when discussing movements. The west wind reflects the wind coming from the west, but instead flowing in the eastern direction.
The planets tend to climb above the Ascendant and migrate over the meridian to the west due to the Earth's axial rotation, although they simply travel in the same direction.
Likewise, the signals tend to fly in a westerly direction though they do not necessarily travel at all. If we conclude that the Sun is in Taurus, we are not necessarily concerned about the Sun's path or its location, but about the position and travel of the Earth as determined by the Sun.
