It seems like internally they have a lot of 'product paralysis', unlike say Facebook which is happy to experiment with totally random things sometimes. That sai

It seems like internally they have a lot of 'product paralysis', unlike say Facebook which is happy to experiment with totally random things sometimes. That said over the last couple years things have been improving on the 'shipping new product/product changes' front for Twitter. Also to be fair when Twitter's user-facing UI seemed stagnant they were building the ad system, etc.