One of the issues with the traditional going barrel is that the barrel arbor only rotates while the watch is being wound. When running, the barrel rotates as the mainspring unwinds, and the arbor remains stationary.
For this reason, any jeweling on the arbor of a going barrel can only benefit the mechanics during the winding action. Despite this, many manufactures fitted barrel jewels on high-grade watches simply to inflate jewel counts.
The safety barrel and motor barrel systems resolve this issue, allowing the jewels on the barrel arbor to be beneficial while the watch is running.
In a response letter to a watchmaker inquiring about the barrel jeweling in 1903, the Elgin National Watch Company identifies the impractical jeweling of going barrels in comparison to the jeweling on their new safety barrel, specifically addressing the full-plate “Father Time” movement:
“Your letter of May 19th is received and we note your inquiry as to why we do not jewel the barrel arbor of our Father Time movement. In the full plate 18 size model the barrel arbor is stationary excepting when the watch is being wound and consequently there is no wearing friction on these pivots when the watch is running and we therefore cannot see that jewels would have any value. In our ¾ plate 18 size model, however, the first wheel is rigidly attached to the barrel arbor and turns thus causing a friction on these pivots when the watch is running and we have therefore jeweled these pivots.”Response Letter from the Elgin National Watch Company, May 23, 1903