This is such an easy question to answer. Which boutique or clothing store would have the selection of styles that I can find in the McCalls, Butterick and Vogue pattern catalogues? What’s more, I can make these styles in the fabric of my choice and in the colour that is most flattering to me. I can select the correct size and if necessary can alter to fit perfectly. More generous seam allowances can be added to cope with fluctuations in weight (manufacturers tend to make them skimpy). I can bask in the satisfaction gained from producing an outfit that attracts compliments. Most importantly I can sew at a fraction of the cost that I could buy the equivalent garment in ready to wear. How do I know all this, because I have been sewing since I made my Mum a satin pyjama case when I was six years old!