Businesses fail to get traction for product reasons, business fail to grow/thrive because the mis-managed complexity makes changing the system too expensive. Ex: well, i'd love to build you that feature, but then i'd have to change x, y and z and there are no tests for y or z because we thought it would unnecessarily slow us down.. so it will take 3 months instead of the 3 weeks that hotshot rails dev you just hired said it should.