看起来playing up好像可以指任何没有正常运作的东西。

Helen: So it seems playing up refers to anything that's not working or behaving as it should.

youdao

定义：一件有缺陷的产品，或是任何无法很好使用的东西；一些经常坏的东西，尤其指车。

Definition: a defective product, or anything that doesn't work very well; something which breaks constantly, particularly a car.

youdao

因此，我说我们没有学到任何东西是指，我们没有改进当时的移动互联网，而是抛弃了它，转而进入了一个全新的领域。

So when I say we didn't learn anything I mean we didn't improve mobile Internet available at that time but we shifted away from it into a whole new space.

youdao