In many cases I've seen staff laid off but replaced with more expensive overtime or contractors.  The real causes of unacceptably high costs are seldom really dealt with. 

The "Achilles heal" of lean manufacturing is usually reliable operation of the plant and equipment.  Without highly reliable performance from the assets themselves the objectives of lean - removal of waste, cannot be achieved.  If equipment is unreliable, then inventories of work-in-process and / or finished goods must be maintained to accomodate the frequent and sometimes lengthy downtime incidents.  Optimizing your maintenance department to "fight fires" faster isn't cost effective yet it is the choice that most companies make.  Rather than get to the root of the reliability problems and deal with them proactively the choice is often to deal with them reactively.  Fix the failure and then do some form of root cause failure analysis.  Of course that works but it is always after the fact.  You never quite catch up with all the failures and never quite move to a steady state smooth operation.

Reliability and reliable performance is achievable. High levels of plant availability will result but more importantly, sustainable long and incident free production runs depend on it.  In addition to enabling lean reliability also leads to improved performance in the areas of safety and environmental compliance.