The guitar sweet spot
There is a saying "the devil is in the details." Well, it is also true that "God is in the details." If you don't know the details, you get Hell. If you know them, you get Heaven. Here is a detail for guitar players.
When you put a finger down on a string to play a note, you must be very aware of the exact spot on your finger that touches the string. For every playing situation, there is one spot on the finger that is the best, that gives you the most pressure on the string for the least amount of your effort, which translates into better playing. There is one spot, which you can sense if you pay attention, that leverages the weight of your arm just right for the position your fingers need to be in. For example:
When you play a first position G chord, your 2nd finger needs to overlap the string a bit, not go straight down on the tip. This is because you will be pulling it toward the 1st string when you place your 3rd finger on the 1st string. If you put it down on the tip, it will come off the string when you place the 3rd finger.
However, when you play a scale, such as the 2nd position G scale, your 2nd finger, which starts the scale, needs to go down right on the tip.
Just as being on the right spot leverages the weight of the arm, and allows you to play with minimum effort and maximum relaxation, being on the wrong spot will have the opposite effect. Being on the wrong spot can tense up your entire arm, greatly hindering your playing ability.
Work with this concept, and you will discover many things
"Great things can be done by great sacrifices only" - Swami Vivekananda