I meet throughout the day in the gym floor trainees who cares too much about exercises that improve their desired body parts.
Exercises selection is important but right techique needs to be applied in order for that to be true. If you do not do an exercise with the right technique it doesnt really matter which one you do first.
In addition to that, Effort level plays a huge impact when training to improve body composition. Setting the right training volume over a period of time and training near failure is essential for improving body musculature.