When is it particularly important to check blind spots?

Checking blind spots is particularly important before merging or changing lanes because it is during these maneuvers that a driver is most likely to encounter vehicles or obstacles that may not be visible in the regular rearview and side mirrors. Blind spots are areas around the vehicle that cannot be seen while looking forward or through mirrors, often located directly behind and to the sides. When changing lanes or merging, a driver needs to ensure that there is sufficient space and that no other vehicles are in the blind spots. Failing to do so could result in collisions with neighboring traffic that might be obscured from view.

In contrast, checking blind spots is less critical when stopping at a stop sign or during low traffic hours since the likelihood of vehicles being in those areas is reduced. While adjusting to changing road conditions like driving in rain does require heightened awareness and caution, it does not specifically necessitate checking blind spots as part of the driving process. Thus, the most crucial time for this action is indeed when merging or changing lanes.