I watched probably six hours of soldering tutorials before my joints started looking right. The things that actually changed my technique was using flux even when the solder wire is rosin-core (especially for rework and for stubborn joints), using the right tip size (most beginners use too small a tip which loses heat on contact), and heating the pad and component together rather than just touching the iron to the solder. The bad joint look is cold solder and it's almost always from not enough heat contact time, not from wrong temp. A proper joint is shiny, smooth and volcano-shaped. What resource actually clicked for you when you were learning?