Cranes & Access reported on a crane overturn in Lichtenstein, Germany in March. The crane was traveling close to the embankment of a stream when the swinging load (a large concrete panel) caused the crane to overturn.
Some cranes can lift without having the outriggers set, and some can travel on tires with a load suspended. Pick and carry sounds good in theory, but the ground through the route of travel must be firm enough to support the weight of the crane and load--meaning the ground through the route of travel must be level within 1% grade. Obviously, the ground this crane was traveling on was neither firm nor level enough.
From the photos it looks like the outrigger beams may have been extended on the embankment side of the road. This is an old trick sometimes used by operators to try to keep the crane from turning over while doing something improper. The load was reported to be swinging, meaning the road was not level and the load was not secured to the front of the crane as required.
This shows how easily things can go awry when proper safety protocols are not observed, even on "simple" everyday lifts. Fortunately in this instance the operator was not hurt, and firefighters' quick response prevented contamination of the stream.