What must be done after a vehicle's oil level is checked?

After checking a vehicle's oil level, it is essential to replace the dipstick and secure the engine cover to ensure that the engine remains protected and clean. Leaving the dipstick out or failing to properly close the engine cover can expose the engine components to dust, debris, and moisture, causing potential damage over time. Additionally, having a secure engine cover is crucial for safety, as it prevents any accidental contact with moving parts while the engine is operating. This practice aligns with proper vehicle maintenance protocol, which emphasizes the importance of ensuring that all components are correctly secured after servicing.