Here's why:

* Living organisms reproduce to create offspring and pass on their genetic material.

* Viruses cannot replicate on their own. They need to hijack the cellular machinery of a host organism to create more virus particles. This process, known as viral replication, is essential for their survival and spread.

While viruses do share this characteristic with living organisms, they lack other defining traits of life, such as:

* Cellular structure: Viruses are not made of cells.

* Metabolism: Viruses cannot produce their own energy or carry out metabolic processes.

* Homeostasis: Viruses do not maintain a stable internal environment.

Therefore, the ability to replicate is the only characteristic viruses share with all living organisms. This makes the classification of viruses as living or non-living a complex and ongoing debate.