For the past five years Twitter engineering has been focused on two things: rebuilding the infrastructure and building an ad platform. They nailed both of these

For the past five years Twitter engineering has been focused on two things: rebuilding the infrastructure and building an ad platform. They nailed both of these. But unfortunately that left little time for product engineering. Add in the revolving door of heads of product and it's no surprise there hasn't been much substantive change to the product.