Flexibility requires two sub-skills: strength in end range and the ability to actively decrease muscle tone under tension. These two skills are built in almost opposing ways. If you only practise one, flexibility progress inevitably plateaus.
First find your type. Then tap the button underneath to get your specific flexibility approach.
Not sure? Relax into your deepest supported stretch, then try to lift out of it on your own. You can always lift up actively, but relaxing deeper into it is impossible? You're tight. Your passive flexibility is way ahead of what you can actively hold? You're loose.