The best defense is a good offense and the best good offense is a pile of artillery shells.
Tack this one up to "Big L for Russia" this is a crucial propaganda and logistical failure for Putin, especially since the word that has to be coming back from the Russian front can be nothing other than silence or "they are sending us out to die without even the artillery our grandfathers were given in WW2".
Not a good time to have news of a fire at one of your crucial artillery factories.