Although gym equipment is designed to work your body they only work one or two main muscle groups at a time. The downside is that it requires a little effort from the core and stabilizing muscles to use machines and their overuse can lead to imbalances, poor posture and sometimes injury.
The best equipment to use is free weights and other pieces of equipment that allows the body to move three dimensionally outside the restrictions of a gym machine. It takes more effort and intensity to do the same movement without a fixed machine and the calorie demand is much greater. Some exercises that don’t involve machines have a functional carryover to everyday tasks.
For best results stay away from machines in the gym that dictates the movement path for you.