Russia has been undergoing major military reforms since 2008. Between then and now Russia has replaced lots, but not all, of its aging Cold War (1948-91) era gear, some of it dating from the 1970s. Army, navy, air force and SRF (strategic rocket forces) have all benefitted in very visible ways. On the downside, a lot of elderly systems are still in service and more older aircraft, ships and vehicles were retired than replacements provided for them. For example, the air force had 2,000 fixed wing combat aircraft in 2008 versus 1,200 in 2020. That’s because the air forces only received 570 new fixed wing aircraft and 320 older refurbished and upgraded aircraft. This means about 75 percent of the smaller fleet of fixed-wing aircraft are modern. Not modern enough, because Russian warplane tech still falls short of Western equipment.
There is also the question of priorities. Russia has put more of their meager defense budget into modernizing SRF missiles and launch facilities, including building a new generation of SSBNs (nuclear powered missile subs) and SLBMs (sub launched ballistic missiles.) Combat aircraft were not the first priority and had to do the best they could.
All this vigorous reform was made possible because Russia was embarrassed to discover serious shortcomings in its forces during the 2008 invasion of neighboring Georgia. Russian leaders ordered an intensive review of current forces and what changes had to be made. Another thing that worried Russia was that their performance in Georgia might have been far worse if the best Georgian troops, 2,000 American trained professionals, were not in Iraq when the war was fought. The Americans had not trained the Georgians for a war against invading Russians. That was considered impractical. The entire Georgian armed forces consisted of 35,000 troops, while the Russians had over 100,000 in the area. If the Russians wanted to invade, the best the Georgians could do was kill as many Russians as they could, and then surrender. The 2,000 Georgian troops in Iraq would have helped with that, but not changed the outcome. More importantly, Russia had lots of troops and commanders with years of recent irregular war experience in Chechnya.
While the Russians achieved their objectives in 2008, their military experts found a large number of mistakes and lost opportunities. Against a more formidable opponent, these flaws might have led to a defeat, and an ugly one at that. But the Russians knew they were going against an outnumbered opponent who was not equipped or trained to deal with this kind of operation, and did not expect the Georgians to do anything surprising.
On the bright side, the Russian military demonstrated great resourcefulness and innovation before and during the invasion. This included the strategic planning, because the war was a set-up. Russia used only one infantry division for the invasion, and had held training exercises in July. The Russians pulled off a "strategic surprise" against the Georgians, and for this the planners could be proud. However, when the performance of equipment and weapons was scrutinized it was found that Russian troops performed far better than their cold war era weapons and equipment. This was particularly true with the air forces.
Although the Georgian anti-aircraft units brought down some Russian jets, the Russians basically ruled the skies and used that to constantly pick apart Georgian defenses. It was Russian air power that prevented the Georgians from mounting an effective defense. Yet it was the Russian Air Force that got most of the criticism for poor planning and execution. While Georgian ground forces were pushed around by the Russian invasion, Georgian air defenses were noticeably more effective. The Russians admitted to losing four aircraft; three Su-25 ground attack jets and a Tu-22 bomber flying a reconnaissance mission. Most, or all, appear to have been brought down by the SA-11 (BukM1) surface-to-air missile systems obtained from Ukraine. The Georgians also have some Tor-M1 systems, also obtained from Ukraine.
Russian intelligence did not identify and locate these Georgian air defenses before the war. Russian pilots were led to expect that there would be no resistance. The Russian pilots had not prepared to go after these Georgian systems with anti-radiation missiles and other air-delivered weapons. The Russian Air Force also made little use of air and space photography to scrutinize the battlefield. They discovered, too late, that the abundance of vegetation down there disrupted the use of their laser guided bombs. A lack of training in delivering smart bombs and missiles also led to poor performance of these expensive weapons.
The overall commander of Russian forces apparently did not, or could not, get the air force to develop an attack plan that would do it by the book. This would include finding and attacking Georgian headquarters and communications facilities. This left the Georgians able to respond to the Russian attack and inflict more casualties. Fortunately for the Russians, the Georgians were outnumbered by a force of more experienced Russian ground troops. This masked the failures of the Russian Air Force.
It is interesting that Russia was unable to come up with effective countermeasures against missile systems they had designed. The Russians knew of Ukrainian arms exports to Georgia, and the presence of the SA-11s and SA-15s. This indicates a failure of communication between the SVR (which collects intelligence about foreign nations) and the military high command. No point in collecting all that information if you don't use it when you have the opportunity.
It turns out that there were numerous failures of intelligence. While the Russians were preparing for action against Georgia, the timing of the Georgian invasion of South Ossetia caught the Russians by surprise. When scrutinized, the Russian commanders in the area were found to have been slow to react. Once the Russian response did kick in, it overwhelmed the Georgians. But, once more, as Russian planners point out, a more numerous or experienced opponent could have defeated the Russians, and all the Russian flaws would have become obvious immediately.
The Russians are eager to fix a lot of these problems, but they are hampered by the presence of many Cold War era officers who came up in an atmosphere of laxness and poor supervision. In short, the "corporate culture" of the Russian military is in disarray. It has to be rebuilt, and Georgia may, or may not, provide the incentive to do so.
When Russia sent troops into Syria in 2015 it soon became clear that the lessons learned from 2008 and the military brought with them analysts to monitor performance, compile data and prepare for another round of reality-based reforms.