Inkscape is a powerful tool. Born in 2003 and developed has been actively since then, but it never had an actual UX and design work behind. Lots of new, amazing features have been added in every version of the software. Most of its features have been added piece-meal over the years with out much thought about consistency. For many designers (non Inkscape users) it seems to be unstable, not proffesional, inmature and with a lack of features compared to its propietary competition. The reason: its usability and design.