Here's why:

* Rust (Iron Oxide) is formed when iron reacts with oxygen in the presence of water (or moisture). This chemical reaction is called oxidation.

* Cold or heat can influence the speed of the reaction, but it's not the primary cause of rusting.

Here's how temperature affects rusting:

* Higher Temperatures: Rusting occurs faster in warm or hot conditions. This is because the molecules move faster, increasing the rate of the chemical reaction.

* Lower Temperatures: Rusting still occurs, but at a slower rate in cold temperatures.

To prevent rusting, you need to:

* Keep metal dry: This prevents water from being present for the reaction.

* Protect metal from oxygen: This can be done by using coatings like paint, oil, or grease.

In summary:

Metal rusts in the presence of oxygen and water, regardless of the temperature. While cold or hot temperatures influence the rate of rusting, they are not the primary cause of it.