How to select a BPM (Business Process Management) product?

I have been working on implementing BPM since 2005 and one of my tasks as BPM Architect leading the BPM practice in my company was to do vendor comparison of software products and publish Accenture's  POV (point of view) about the software. As architects we also recommended best fit software to our client and our solution architects. BPM is one of the products that I have evaluated multiple times. I received an email from software engineers on how to select a BPM product and I decided to post my views on 'Software Product Selection' based on how we evaluated software for our clients, most of the clients were one of the Fortune 100 companies.
                     Gartner's Magic Quadrant & Forrester's Wave are 2 popular software vendor evaluations that I usually refer to get an idea of features and offerings of software products. These product evaluation and ranking are purely for reference as they consider many different criteria to position a software product as Leader, Visionary, Niche player or Challenger as Gartner classifies them. 

Here is Gartners Oct 2017 Magic quadrant for Intelligent Business Process Management Suites

And this is the Q1 2018 Forrester Wave Report

In the above chart I would not really worry about the X & Y coordinates of the software as long as they are both are Leaders quadrant or even in Niche Player or Visionaries or Challengers Quadrant if they offer the features that are important for my solution.  In fact, BPM is fast changing landscape and new features are offered almost every quarter.

If you are out to select a BPM product my recommendation is to
1) List key requirements of your solutions (do consider long term requirements as well)
2) Go through vendor comparison reports and product manuals and evaluate each vendors product features, have a look at the demo videos of these vendors
3) Select top 2 products that match your requirement.
4) Implement a prototype, ask your business users to go through the prototype  and then shortlist the BPM product.
5) Some vendors claim to have a various feature but in reality the feature could be part of their future enhancements and you may have to wait for 6 to 12 months to implement the feature. So make sure you discuss all the critical requirements of your solution with the vendor and ensure they are supported in the software version that is you intend to use.

For all you know your architect may recommend Pegasystems , or Appian or  IBM BPMor even TIBCO Active Matrix BPM based on your requirements. So do not blindly go by the Forrester Wave or Gartner Magic Quadrant, do your homework and you will not regret it.