There can be many problems due to production issues such as Ore...

There can be many problems due to production issues such as Ore being tipped over waste dumps by mistake on many occasions.
Dig units digging ore blocks incorrectly and or without the presence of a Geologist causing a different set of issues.
Machines/operators having major accidents or break downs causing a pit to shut down hence no production for extended periods.
Poor engineering designs and frequent visits from the mines department to investigate serious incidents.
Retaining staff is also a big issue, all these things impact a business and need to be addressed.