SoilYour soil is important. Herbs need well drained soil. That means if your soil has a lot of clay in it. You really need to add organic compost to the mix. It adds nutrients to the soil as well as allowing it to drain easier. (The secret to finding if your soil is high in clay is check to see how long it takes water to drain. If it takes more than a minute, you may need to add some compost.)
If you want your herbs to have a great flavor, you need to provide them with organic fertilizer and water. Water your plants when the soil seems a little dry around the edges. Be careful not to over water. And fertilize it once or twice during the growing season.
Most herbs are natives of Mediterranean climates. That means it's just in their makeup to like warmth and plenty of sunshine. If you want great tasting herbs make sure to provide your plants with lots of natural sunlight.