Historically a good level of drawing was required in order to become an architect. Plans used to be drawn using a board and paper.
However, the introduction of Computer Assisted Design programmes for use on the computer, generally means that architects do not have to be able to draw free hand. Nearly all drawings are done using a computer.
So it is not impossible to become an architect whilst being unable to draw, but it certainly is of benefit. Sometimes, a drawing may be very quickly required on a building site. For example, it may explain how a joist should be located in relation to other beams etc, in a way that can be much more succinct than having to explain the concept in words or written form. It can also be easier for builders to understand. This is more technical drawing, the techniques of which can be taught and practised over time, so it is possible to become an architect without qualifications in art.