To make a **left turn**, it is essential to have **sufficient visibility**. This is crucial because you need to ensure that there are no oncoming vehicles that could pose a danger. If you cannot see well, for example, due to a curve, a crest of a hill, fog, or heavy rain, you should not make the turn. Lack of visibility can prevent you from correctly assessing the distance and speed of approaching vehicles, which increases the risk of accidents.

Furthermore, in situations where visibility is limited, such as in tunnels or level crossings, changing direction is prohibited. Safety should always be the priority, and having good visibility is essential for making safe driving decisions.