Because digging while on tires intrinsically causes the machine to rock, and the swinging weight of the backhoe could cause the vehicle to tip, most backhoe loaders use hydraulic outriggers or stabilizers at the rear when digging and lower the loader bucket for additional stability. This means that the bucket must be raised and the outriggers retracted when the vehicle needs to change positions, reducing efficiency. For this reason many companies offer miniature tracked excavators, which sacrifice the loader function and ability to be driven from site to site, for increased digging efficiency.