Limp mode is not the fault. Limp mode is the truck protecting itself because something upstream has been ignored for a while, usually a diesel particulate filter that has never been given the chance to complete a regen.
A DPF burns off soot when exhaust temperatures get high enough for long enough. Short local runs, a lot of idling, and cold coastal mornings all work against that. Soot builds, back pressure rises, and the ECM starts pulling power.
The fix in the moment is usually a forced regen. The fix long term is a driving pattern that gives the truck a chance to complete a passive regen, plus a look at whether an EGR or sensor fault has been quietly preventing regens for months.
If your fleet is racking up limp mode events, that is a maintenance schedule problem, not a driver problem.
