When parapenting… the launch is the most critical decision of all, and you much pick “a good moment” to begin the flight.
There are no fixed rules or recipe for the momemt, but more appropriately it must feel right, in your gut.
Some of the elements are: The correct amount of wind in your face, a calm mind, a clear runway, and a firm confidence in your soul as you run off a cliff. When the moment presents iteself, you run resolutely. If the moment does not appear, then you wait, and perhaps even wait until another day.
In English there is an expression that “timing is everything …and means nothing” and while it means simply that timing is critical for success/survival, the second half of the expression (sometimes ommitted) relates that all the proper fundamental training, prepartion, and intrinsic understanding is not sufficient for success/survival.
You must have the element of “a good moment” too.