I've enjoyed every JJP game I've played on location and every game they've produced is remarkable in it's design and construction. But you can't dilly dally around when making pinball games - every single day you're haemorrhaging vast amounts of money. They need to be made quickly and often, which is the only way to succeed in the long term.
When I started at Heighway Pinball in 2013, Stern had just released Star Trek. In the time it took us to get Full Throttle into production, Stern had released 5 more games. When Full Throttle did finally sell, we only shifted about 100 units. At this point the company was heavily in debt and there was no way back.
Make 'em quick and make 'em often, it's the only way.