Incorrect machine selection can result in delays due to not being able to finish the job, or inappropriate application of an existing machine which will slow productivity and may result in a lost time accident. Some other common causes of worker downtime are: running out of fuel, contaminated fuel, machine not charging due to using the incorrect charging point, excessive flat battery, machine damage during operation, or a simple thing such as loss of ignition key. Each one of these issues causes varying degrees of unnecessary and costly downtime. Thorough planning, proper supervision, familiarization and quality training are critical to ensuring a safe, productive and profitable worksite.