When Russia launched its offensive on Ukraine last year, the Kremlin–– and many Western observers––expected it would not be long before Russia captured Kyiv and ousted President Volodymyr Zelensky. But at the one-year anniversary of the war, it’s become clear that Ukraine has not only been able to withstand the assault—it’s succeeded in regaining control of key territories.
Russia’s army had some successes—including attacks on airfields and civilian infrastructure—but experts detail how poor planning, faulty intelligence, and a misunderstanding of the strength of Ukraine’s resistance and Western support all but ended any chance Russia had of a swift victory.
Here are the biggest military mistakes Russia has made so far in the war.
A Lack of Logistical Planning
At the start of the war, Russia believed the operation would last a few weeks at most and failed to prepare for a long offensive. This lack of long-term planning proved to be a fault as the war dragged on.
“It has taken the Kremlin months and months to start to belatedly treat this as the large-scale conventional war it is, rather than a quick operation to ‘de-Nazify’ Ukraine,” says Mason Clark, a senior analyst for the Institute for the Study of War.
“The Kremlin believed its own propaganda,” Clark says. “It thought it was going to be welcomed by the Ukrainian population as liberators and that the Ukrainian military would collapse.”
The poor logistics system led to failures across the board; troops were not properly supplied and left without an established chain of command. “Russia’s original sin was how they structured their forces at the beginning of the invasion,” says Clark. “They didn’t take time to set up proper logistics chains and just sent in ad hoc units.” As a result, Clark says, troops were basically competing with each other for resources.
Read More: How Russian Media Spent a Year Selling the War
And when Russia failed to seize and hold major territories, several senior military officials were fired or suspended as a result The poor chain of command and constant reshuffling had an impact on the military’s adaptability.
A New York Times investigation says that Russia fired missiles based on old maps and bad intelligence, a move that did little to hinder Ukrainian air defenses. Russian soldiers called home on their cell phones, allowing Ukrainians to track their locations through the signals.
“There’s a disconnect between what Putin wants and what the Russian military is capable of,” says Mark Cancian, a senior adviser with the CSIS International Security Program.
Underestimating the Ukrainian Resistance
Russia deeply underestimated the strength of Ukraine’s resistance, a move Cancian says doesn’t come as a surprise. “It was not unreasonable to underestimate them.” Before the war, Ukrainians themselves viewed the government as inefficient and corrupt—Zelensky’s approval rating stood at just 27 percent.
“If you had told people Zelensky could be the greatest wartime leader since Winston Churchill, people would have laughed at you,” he says.
Zelensky’s decision to remain in Ukraine, and his impassioned speeches delivered over social media, inspired many Ukrainians to push back against Russian invasion.
The Ukrainian army also proved to be far more adaptable than Russia expected. “Russia certainly underestimated how flexible the Ukrainian military was,” says Clark. “Throughout the war, they’ve done an excellent job of shepherding their limited forces to where they’re most needed and not impaling them on pointless battles, which is what the Russians have been doing.”
NATO’s United Front
In December 2021, Russia presented a list of demands to the West in order to diffuse mounting tension in Ukraine, which included a ban on Ukraine entering NATO and a limit to the deployment of troops and weapons to countries on its Eastern flank.
Russia was expecting a reaction similar to its 2014 annexation of Crimea, when the United States and the European Union enacted sanctions against Russia. Instead, NATO countries stepped up to the plate, sending weapons, ammunition and military equipment, along with billions of dollars in aid. The U.S. alone has sent more than $24.9 billion in security assistance to Ukraine since the beginning of the invasion.The Pentagon marked the first anniversary of the invasion with a $2 billion package of long-term security assistance for Ukraine that includes more rounds of ammunition and a variety of small, high-tech drones.
“Putin certainly thought he had a better chance of dividing Europe than he actually did.” says Clark, “Instead Western support has been unified for Ukraine.”
Squandering Weapons
Russia’s flawed military strategy has led to a catch-22 for the military, says Clark. “They’re facing this challenge where they need to concentrate munitions, fuel, and other supplies close to the front line, but that exposes them to very accurate Ukrainian artillery fire and airstrikes.” Clark says.
The help of the U.S.-supplied HIMARS rocket-systems allowed Ukraine to hit dozens of Russian ammunition depots. HIMARS, which stands for High Mobility Artillery Rocket System, is one of the world’s most advanced rocket artillery systems, effective for attacking stationary targets in a concentrated area.
“When the Russians try and place their supplies further away from the front lines where they can’t be threatened by Ukrainian forces, they’re unable to properly supply their frontline troops.”
The new challenge for Russia is replacing the destroyed munitions. “Russia can certainly replace standard pieces of equipment [like] ammunition, rifles, and some basic armored vehicles.” Clark says. “They’re going to really struggle to replace all of the higher end pieces of equipment that they have lost, like advanced tanks and missiles, due to the cost of sanctions.”
Despite these challenges, Clark notes that the pressure is still on for Ukraine to launch a counteroffensive and receive more Western support before Russia begins to fix some of its errors.
“Over the long run, Russia will be better able to bear the costs of this war lasting until 2024 or 2025.”
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Write to Simmone Shah at simmone.shah@time.com