Generally, I dislike playing the “quote game”, but here is a passage from Lenin’s Where to Begin that speaks to this question:

“We have spoken continuously of systematic, planned preparation, yet it is by no means our intention to imply that the autocracy can be overthrown only by a regular siege or by organised assault. Such a view would be absurd and doctrinaire. On the contrary, it is quite possible, and historically much more probable, that the autocracy will collapse under the impact of one of the spontaneous outbursts or unforeseen political complications which constantly threaten it from all sides. But no political party that wishes to avoid adventurous gambles can base its activities on the anticipation of such outbursts and complications. We must go our own way, and we must steadfastly carry on our regular work, and the less our reliance on the unexpected, the less the chance of our being caught unawares by any “historic turns”.”