And for those that don't want to read the whole article …
The simplest (and most proven) way to address the of coaching to high performance, and ensuring the right stuff is being worked on is through the assignment of a Scrum Master and a Product Owner. When backed by proper training and support these roles will allow you to establish high performing teams which are focused on doing the most important work now.
Pragmatically it is sometimes not possible to staff these roles fully. If this is the case then you should also lower your expectations as to what you are going to get from your agile transformation. The impact is mostly felt in terms of how long it takes for things to get visibly better but might also result in a failure to improve at all. Not having these roles will also result in a your teams seeing problems, the very problems these roles we designed to address.