I realized that I started lowering the leg during the last exhaling. 5 breath one shall hold this pose, too, 5 full breath. It's so important to observe oneself. Now I lower the leg after the last exhaling.
This pose shapes the body.
It exercises the mind, willpower. (The face is relaxed.)
Strong legs are important, this asana helps to get them.
There is a muscle between leg and body, a hip muscle. Here one can exercise it. It's necessary if one likes to do the vinyasas. It's amazing how all the asanas are connected.
To point the foot helps. To breath deeply helps, too.