Can it be design-less?

Have just spent 20 minutes arguing with my colleague about whether big-good-selling and very complicated piece of software can have bad design or not. Personally when I do have produce poor designs that projects never become good or used just because they are badly designed or are bad by design That is almost the same in this case

In contradict my colleague persisted on fact that still this (we discussed it on a concere example, I'll not publish the name due to ethical reasons) huge code collection is poor by itself, inside and outside. He've seen the code. What I think is that the code he've seen was actually far not the software core code. Just a plugin stuff or alike. If company has a policy of not spending much attention to plugin like stuff the latter can pretty be not designed properly at all while the project itself remains perfectly maintained.  So we didn't agree at last.

Well, I think if that company-head-politicians can put a little attention to minor stuff it just confirms how sure and stable they feel themselves on the market. Still it brings some shadow on how it might be expected to be.