One of the joys of watching Winter Bowls at Sturt is to note that many bowlers send their bowls off on the journey down the rink, with the bowl upright, not on a lean.
Queensland bowls coach R. C. Harrisom in Coaching Basics and the Etiquette of Bowls (2021), notes the importance of the bowl traveling "on an even keel without wobble" and along the selected line.
Similarly, the Warburton Bowling Club https://warburtonbowls.bowls.com.au/coaching-tips/ highlights the importance of delivering your bowl on its running surface, not tilted to one side, avoiding "that dreaded wobble".
See photos below of Sturt members at Winter Bowls on Wednesday 10 June eliminating the wobble.