Yeah! Definitely. It’s Khrushchev’s fault.
Let’s be honest here. His decision caused unintended repercussions on the USSR. On 15 October 1962, a US spy plane discovered a missile site in Cuba installed by the USSR. When Kennedy eventually received the news, he then ordered a naval and air blockade on Cuba, meaning that all importing and deployment of Soviet ‘offensive weapons’ would not be able to reach Cuba. This caused the immediate escalation of tensions with the Soviet Union and Cuba as they believed that the US was aiming to launch a full-scale act of war between it and the USSR. These responses of the USSR and Cuba have also sharply increased the possibility of the nuclear war, pushing the world dangerously close to it. Moreover, eventually as Khrushchev decided to remove the missiles in Cuba, he greatly lost his prestige and credibility as the USSR leader because the government saw his action as compromising too much in the negotiation, making the USSR appear weak.
Thus, his decision can be considered as his error in judgement as it has backfired against him. The reaction of JFK after he discovered the missiles caused the conflict between the two nations to deteriorate very quickly, almost to the point of full-scale war. It further heightened the tension between the superpowers, as well as, created an unprecedented fear in the world.
No! He did the right thing
Nevertheless, the act of placing missiles in Cuba has removed the USSR’s security concerns and increased its political leverage. The USSR has become a bargaining chip against the US as it forced JFK to impose naval blockade which prompted the exchange of letters between the two leaders. In October 1962, after a series of negotiations after placing the missiles in Cuba, Khrushchev eventually decided to remove the missiles from Cuba. The fulfilled promise of the US of not invading Cuba was also achieved. Furthermore, the US had also removed the Jupiter missiles from Turkey in 1963. Even though the agreement was kept secret, the threat of Jupiter missiles was removed from the USSR. The USSR also maintained its relationship with Cuba as well as Cuba remained to be communist and valuable ally to the USSR in the America region.
Hence, Khrushchev’s decision was not a mistake as the crisis had succeeded to alleviate the USSR’s fears of being attacked by the USA. The removal of Jupiter missiles also meant the removal of nuclear threat at its close proximity as Turkey bordered the USSR. The presence of a Soviet ally, Cuba, in the region also benefited the USSR greatly as it boosted the USSR’s prestige and would also counteract the USA’s sphere of influence in the region, helping the communist bloc to gain political leverage against the USA.
I personally believe that Khrushchev's decision to put nuclear missiles on Cuba was not an error from his judgment as the long-term benefits the USSR gained clearly outweigh the harms and the losses. The impact of the discovery of the missiles was the increase in tension that was shared by both superpowers and the rest of the world. However, most benefits were gained by the USSR alone. For example, the USSR had gained political leverage and its long-term security after placing the missiles in Cuba. Therefore, it was definitely not the error from Khrushchev's judgement.