From Paragon's IPDB page:
"Paragon' is the first widebody production game from this manufacturer.
The standard version of this playfield has four flippers as shown on the flyer. An unknown quantity of the games shipped to Europe had only three flippers. In this version, a ball guide and a single post replaced the upper right flipper, and the flipper assembly was not installed. In addition, a mini-post was added at the opening beneath the pop bumper in the Beast’s Lair to make it more difficult for the ball to leave the playfield that way.
We asked designer Greg Kmiec to comment on why the 3-flipper version was created. He replies:
I wouldn't have originally designed Paragon with that lower right section that way because it looks like the pinball could get stuck between those two wire forms.
If my memory serves me correctly, I seem to recall that the Italian, French and German markets were quite strong for Bally during that period and Bally was often visited by various foreign distributors. I recall that they relayed the fact that their players liked to hold the pinball by the flippers. The way it was relayed to designers through interpreters was that their players liked to hold the pinball on the flipper, take a drink of beer and brag to other players about the skill shot they were about to shoot. That couldn't be done with the original Paragon design. I tried something different with Paragon, since it was Bally's first wide-body game. It was relayed to Bally that the foreign player preferred one return lane on each side at the bottom of the game that "returned" the pinball to the flippers for a playfield skill shot. This type of design became known within the industry as the "Italian Bottom." It was used extensively then throughout the industry and is still in use today.
I do seem to recall adjustments being made to Paragon for foreign games [to have the "Italian Bottom"]. I don't recall how many were changed or if they were changed for only one country or one distributor, but they were definitely changed in the factory on the production line. It might have been due to a combination of two factors: the foreign distributors requesting something their players wanted and Bally realizing a cost reduction on the Bill-Of-Materials by eliminating a flipper. Bally might have been willing to change part of a production run just to sell a new wide-body game.
Reportedly, all Paragon games in France have only 3 flippers."