Here's why:

* Proximity to the Sun: Venus is the second planet from the Sun, making it very close to our star.

* Brightness: Venus is extremely bright due to its dense, reflective atmosphere.

* Visibility: Because of its brightness and proximity to the Sun, Venus is often visible only shortly after sunset or before sunrise, when it's high enough in the sky to be seen above the Sun's glare.

So, while Venus is a very bright planet, its close proximity to the Sun makes it difficult to observe at other times.