Final answer:
Ladders must always be placed on stable bases for safety. Attempts to use unstable bases are against safety guidelines and can result in serious injury.
Step-by-step explanation:
Ladders should never be placed on unstable bases to obtain added height. Doing so can lead to accidents and injuries because the ladder can easily slip or tip over without a stable and level foundation. Safety guidelines clearly indicate that ladders should only be used on stable and level surfaces, and no shortcuts such as using a spotter, securing with duct tape, or setting up for a short time can substitute for proper ladder safety.