If we do not despise him with regard to the whole, we shall commit opportunist errors. Marx and Engels were but two individuals, and yet in those early days they already declared that capitalism would be overthrown throughout the world. But with regard to specific problems and specific enemies, if we do not take them seriously, we shall commit adventurist errors. In war, battles can only be fought one by one and the enemy forces can only be destroyed one part at a time. Factories can only be built one by one.
Peasants can only plough the land plot by plot.
The same is even true of eating a meal. Strategically, we take the eating of a meal lightly, we are sure we can manage it. But when it comes to the actual eating, it must be done mouthful by mouthful, you cannot swallow an entire banquet at one gulp. This is called the piecemeal solution and is known in military writings as destroying the enemy forces one by one.