Operating Weight Capacity is the "normal" max weight that can be lifted safely.
This assumes the loader is on level smooth ground. If moving, you are moving slow and smooth. If conditions are not optimum, you should reduce the load.
According to the SAE Standard, wheel loaders Operating Weight Capacity is 50% of the Tipping Weight. The Tipping Weight is the load at mid-lift height where the loaders rear wheels lift off the ground.
Tracked Loaders are rated differently. The Operating Weight Capacity is 35% of the Tipping Weight. The reason is that tracked machines are designed to operate on uneven and soft terrain which is less stable.
If your loaders hydraulics are operating properly, you should have no problem lifting enough weight to tip the loader.
If you have a radial lift (not vertical lift) machine, the load moves away from the front wheels as you lift. I can lift more than the tip capacity if I just lift it a few inches off the ground to move it. If I continue to lift, the loader will tip as the load moves out further from the machine.