Yes, weight is more accurate when you have scales however if you are doing something on the fly or don't have scales then volume gets you better results than trying to guess the weight.
My biggest problem with volume recipes is that very often they don't abide to the 250ml cup but use slightly larger or smaller cups, which causes variations. There is also the caveat of not having a measuring cup available just as I previously mentioned not always having scales available.
With all that said, ideally recipes should include both weight and volume measurements at all times.