In questions like this, there should be some demonstration of attempts to avoid human errors. Here we have a massive attack on the whole territory, including regions at the border. We can wait for next actions from Russia - if they'd bring apologies and some good offers - but meantime it's a good idea to keep reaction going. After all, it's the approach proven to be most reliable when dealing with current Russia.
If I told you that a surgeon made two fatal mistakes, you can't conclude from that information whether or not he's made a lot, a little, or an average number of attempts to avoid human error in his work.