Here are some reasons why you should consider changing your mattress:

1. Comfort and support: Over time, mattresses can lose their ability to provide proper support and comfort. If you're waking up with aches, pains, or discomfort, it may be a sign that your mattress is no longer providing the support your body needs.

2. Better sleep quality: An old or uncomfortable mattress can lead to poor sleep quality, including disruptions, restlessness, and inadequate support for your body. A new mattress can enhance your sleep, resulting in better rest and overall well-being.

3. Hygiene and allergens: Mattresses can accumulate dust mites, allergens, and other debris over time, which can exacerbate allergies and respiratory problems. Changing your mattress can help create a healthier sleep environment.

4. Durability: Most mattresses have a lifespan of about 8-15 years, although this can vary depending on the type and quality of the mattress. After this period, the materials and support may degrade, impacting your sleep quality.

5. Sagging and indentations: Over time, mattresses can develop sagging and indentations in the areas where you typically sleep. This can result in uneven support and discomfort, making it necessary to replace the mattress.

6. Changes in lifestyle or health: If your lifestyle, sleep preferences, or health conditions have changed, your old mattress may no longer be suitable. For example, if you've gained or lost weight, had an injury, or developed new sleep preferences, a different type of mattress may be more appropriate.

7. Partner disturbance: If you share your bed with a partner and your mattress is not adequately isolating motion, you may be disturbed by their movements during the night. A new mattress with better motion isolation can improve your sleep quality.

8. Mattress technology advancements: Mattress technology is continually evolving, and newer mattresses often incorporate innovative materials and features designed to enhance comfort and support. Upgrading to a more advanced mattress may improve your sleep.

9. Better value: An older, uncomfortable mattress can negatively affect your sleep, productivity, and overall well-being. Investing in a new, high-quality mattress is an investment in your health and can provide better value in the long run by improving your sleep and overall quality of life.

In general, it's recommended to assess your mattress every 8-15 years and consider replacing it if you notice a decline in comfort, support, or sleep quality. Choosing a mattress that suits your sleep preferences and body type is essential to ensure a good night's sleep.