Russia attempts to restructure its failed combat formations

 ISW:

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The United Kingdom Ministry of Defense (MoD) reported on November 29 that Russian forces have likely stopped deploying battalion tactical groups (BTGs) in the past three months.[4] The UK MoD stated that the BTGs‘ relatively low allocation of infantry, decentralized distribution of artillery, and the limited independence of BTG decision-making hindered their success in Ukraine.[5] ISW assessed starting in April that Russian BTGs were degraded in various failed or culminated Russian offensives, including the attacks on Kyiv, Mariupol, Severodonetsk, and Lysychansk, and later efforts to reconstitute these BTGs to restore their combat power have failed.[6] Russian forces have likely since thrown their remaining combat power and new personnel, including mobilized personnel, into poorly trained, equipped, and organized ad hoc structures with low morale and discipline.[7] The structure of BTGs and the way the Russian military formed them by breaking up doctrinal battalions, regiments, and brigades likely deprived the Russians of the ability to revert to doctrinal organizations, as ISW has previously assessed, so that the Russians must now rely on ad-hoc structures with mobilized personnel.[8]
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A prominent Russian milblogger contended that Russian forces should make use of World War II-era artillery and cheap, inferior-quality military equipment to address challenges in providing for Russian soldiers.[53] ISW has extensively reported on Russian difficulties in providing for the mobilized as well as on Russian equipment shortages.[54] The milblogger alleged that both Russia and NATO states are experiencing weapons shortages and presented cheap, simple, and old equipment of perceived lower quality as a way to “quickly and cheaply saturate the troops.”[55]

Reports from Russian sources indicate that Russia may attempt to use prison labor, overtime, and child labor to resuscitate the Russian military-industrial complex and fill general labor shortages. Russian opposition media source Meduza reported on November 29 that 250 convicts from Sverdlovsk Oblast will serve forced-labor sentences at a Russian tank and armored vehicle construction plant.[56] Meduza separately reported that employees at the plant have been working four additional hours on weekdays and extra shifts on weekends.[57] Zaporizhia Occupation Administration Council Member Vladimir Rogov on November 29 cited a speech by Russian Children’s Rights Commissioner Maria Lvova-Belova that the Russian State Duma will consider a bill amending the Russian labor code to simplify the employment procedure for those under 18.[58] Russian deputies may hope such actions will reduce the severe Russian labor shortage exacerbated by mobilization, on which ISW has previously reported.[59]
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This explains some of the failures of the Russian troops, but not all of them.  The operations in Ukraine have been poorly planned and have exposed not only the weakness of the Russian command structure but also the weakness of Russia's industrial base in providing war material. The defects are compounded by an attempt to throw poorly trained or untrained troops into battle with rusty rifles.

Russia has already gone through much of its military equipment and is trying to improvise such as its recent use of old missiles with the nuclear warheads removed in an attempt to thwart Ukraine missile defense systems.