Yes, you can leave a tablecloth on a table all the time. It's a common practice in many households and venues to keep tablecloths on tables as they not only protect the table surface from scratches and stains, but also add to the aesthetic appeal of the space. However, it's important to ensure that the tablecloth is regularly cleaned to maintain hygiene and its appearance. If the table is exposed to sunlight, consider using a tablecloth made of a fabric that's resistant to fading. Also, if the table is used frequently, opt for a durable, machine-washable fabric like cotton or polyester. It's also worth noting that while tablecloths can add a touch of elegance, they can also hide the beauty of a high-quality table, so the decision to use one should be based on your specific needs and preferences.