What would be Putin's motive in the case of Skripal? And if he really wanted him dead, there would have been a thousand other ways to do it without basically wr

What would be Putin's motive in the case of Skripal? And if he really wanted him dead, there would have been a thousand other ways to do it without basically writing "Russia" with a spray can all over the body. To be clear, I'm not saying he didn't do it. Just that it's not as completely obvious as it seems. Why would Putin and Russia lose billions (because that's the economic impact of the West's reaction) to kill an ex spy in the most damning way?