One of the biggest drivers of the disaster that was Soviet collectivization was a big fear that Lenin was wrong (he was) in his early claims that peasants would support the Bolsheviks.
Classical Marxism is based in part on a hypothesis that a socialist revolution has a number of preconditions, one being an advanced capitalist economy (Russia of course did not meet that), and a second one being that as a consequence of that, a society with a large working class majority (Russia did not meet that either).
Lenin "worked around" this with a pamphlet published in the early 1890's where he argued that Russia was special: In Russia the large number of landless peasants would come to the support of the socialist revolution and make it possible for a socialist party to take control. Coupled with his idea of a "vanguard party" leading the masses, he believed this would allow Russia to basically "skip capitalism".
The big problem with that, of course, was that it never happened: In the elections for the Constituent Assembly arranged by the Provisional Government after the February Revolution, the Bolsheviks got a minority, with almost all their support in the big cities, while the peasants largely voted for more moderate parties - including the socialist SR/Left SR and Mensheviks. So the Bolsheviks went into their coup (the October "revolution" was a coup against the socialist-led Provisional Government; the Tsar had already been in house-arrest for months) in a situation where they must have known that the odds were most peasants would oppose their regime.
Collectivization then must be seen against a backdrop where the Bolsheviks not only had theoretical reasons to want to minimize the peasantry (trying to "leapfrog" capitalism), but also had very practical reasons to want to try to forcibly mold the peasantry into working class: they were afraid that leaving the peasants be would sow the foundations of further opposition.
Lenin relented a bit after the civil war, with New Economic Policy (which allowed limited market economy), but as soon as he died, Stalin pushed collectivization much harder and further, basically on the basis that while he couldn't eradicate farmers, he certainly could do whatever he could to try to turn farming into an industrial job.
So while they undoubtably also hoped to find ways of increasing productivity, it's worth realizing that a lot of decisions they took also had another purpose of basically trying to find a way of "farming without farmers" that was politically important especially for Stalin, and that made many possible concessions that might have mitigated disastrous outcomes completely politically unpalatable for the Bolsheviks because they especially early on feared for their power base. E.g. even the concession they did make under Lenin (NEP) were unpalatable enough for Stalin to reverse them.
It doesn't excuse what they did in any way, of course, but it goes so way towards explaining why they persisted in at times disastrous policies even after they'd clearly learned about the consequences - maintaining power remained more important for them than getting good outcomes.