The problem won’t wait for its solution. It will bother you as long as it exists. And it won’t stop until you fix it. The impact of it will be bigger each day.
After identification of the root cause you know what needs to be solved. You know what have to be checked to confirm that your are going in the right direction.
What’s now? If the problem is big this is not always the moment when you start planning implementation of the solution. Why?
Problem won’t stop its growth the same day when you decide to solve it. It will still expand. And this where you should put your focus on in those first days. You have to stop its growth if this is possible!
If you don’t stop expansion of the negative impact of the problem you may start implement solution and before you will end, there will be nothing worth saving anymore.