Check the late gain win rates. The longer the game goes the more the winrate drops. Early sole source of mobility is literally being gutted, with it the early power is also dropping drastically to the point that kill pressure is pretty well gone till the mobility skill is maxed. She is impossible to assassinate if you are bad or zed (every other assassin doesn't have their kill damage delayed and can easily just save one more hit till post ult or their superior mobility)
The sacrifices come from being extremely susceptible to being blown up, and having their relevant damage potential come from their passive which is easy to deny if you are half decent.