That joint in the bottom left looks dicey at best.
solder joints should be bright and shiny- are you using rosin cored solder or flux?
Your iron might need the temperature adjusting too if possible - dull joints can be a sign that your iron is too hot.
Best thing to do is remove all of the solder from the pot lugs, cut fresh ends on the wire, then twist and tin them. Insert both ends into the solder lug, then solder them both to the pot at the same time.
Also, it’s worth putting a crocodile clip across on the lug you’re soldering as a heat sink so you don’t damage the pot with heat.
Always turn pots to full counterclockwise before soldering them too - this reduces the risk of damaging the track inside with the 200 degree iron..
sorry if that’s a lot, I’m just sharing the wisdom of my years of building, and the stuff that I learnt the hard way when I was starting out.