Kano vs WSJF

How do we decide what to put on the top of the backlog? How can we prioritise one story over another? I have seen many different ways, here are a couple:

1. low hanging fruit: pick the easiest items that can be solved fast. These are not always the most important ones and can lead to technical debt or dissatisfaction of the customer.
2. The loudest yeller: in a group, there is one stakeholder that yells the loudest about their item, silencing the other stakeholders. This leads to a dishonest balloting of items and doesn't put the most important items first. 
3. The managers priorities: in traditional or hybrid organisations that are adopting scrum, managers are about people and projects. This can lead to managers making priorities instead of the stakeholders or customers and thus not delivering the most important items first.

So how can we do a better job? I want to mention two: the kano-model and WSFJ.

Kano

The Kano model is an approach that prioritises stories based on customer satisfaction plotted against functionality.

• In the left top customers is the functionality that brings excitement to our customers. If you invest in those, your customers will be delighted. Mind that not implementing these doesn't lead to customer dissatisfaction. A minimal viable product will not include these functionalities.
• On the right bottom are the basics for the service to work. These are basic functions which are taken for granted. Customers won't be satisfied by these functions, but will become very dissatisfied if they are not implemented.
• And on the top right are the performance functions. The more you invest in these functionalities the more the customers like it. The better the performance the happier the customer.

You can read more about the Kano model on the website of ProductPlan: https://www.productplan.com/glossary/kano-model/

WSJF

WSJF is an abbreviation for Weighted Shortest Job First. I came upon it during a SAFe course. It is based on the idea that we can weigh stories on importance and work and get the most economic benefits. For WSJF we need a bit of simple math. First we need to find out what our CoD (Cost of Delay) is. So how much money will we loose when we don't implement this functionality? We plot that against the job size with the formula: WSJF = CoD / Job size.

It is easiest to make a table with all the functionalities or stories or stuff you want to make, add a column for size, CoD and weight (which is CoD / Job size). After plotting this in the table, the item with the most weight is the most important to implement.

You can read more about WSJF on the SAFe website: https://www.scaledagileframework.com/wsjf/

How do you do your estimations? Which model do you prefer and why?