The invasion of Russia wasn't necessarily a bad idea to start off. The political situation with Russia was falling apart as Napoleon and Alexander were becoming cold toward each other. To make matters worse, Alexander refused to let Napoleon marry one of his sister (causing him to move to marry into the Habsburg family and Marie Louis von Habsburg) and it was becoming known that Russia was flouting the Continental System that was a part of the Treaty of Tilsit. Further, Britain was making headway with Russia diplomatically and offering money to help pay for a Russian army to challenge Napoleon. This would be the continuation of Britain's role in the Napoleonic Wars, that of Mephistopheles to the reluctant allies of Napoleon. Thus, Napoleon was facing a Russia that was arming themselves for war and actively working against the economic system of France that was meant to ruin Britain.

Did anyone think it was a bad idea to invade Russia? No. The matter was that of timing and method. Napoleon famously pushed toward Moscow but the issue there is that of logistics. The land that Napoleon would be going through would be very poor in terms of agriculture, thus the combined armies wouldn't be able to live off the land effectively, thus it was suggested by some to move south through the Crimea (contemporary Ukraine) which had rather good agriculture for the armies to rely on. Further, the timing wasn't that of the season but rather that of aggression; Napoleon would effectively be declaring war against a nominal ally, one ready to stab him in the back, but it still would have looked bad.

The time that Napoleon invaded, late June, is the ideal time to push into Russia. Due to weather, it would have been after the usual rainy season (and doing it earlier would have been a disaster as Russia stays cold well into March), so moving in June worked out but Napoleon wasn't able to hold the Russian army into a significant battle until September 7th, a full two months was "wasted" due to Russian maneuvering.

Despite how history turned out, the invasion of Russia was actually well planned and started with the right intention. Knowing that Napoleon prefers a strong and decisive battle, the Russians prevented him from doing so by using their own knowledge of their own country while moving in an area that would have worked against French logistical policy of foraging.