I've always thought everyone knew this simple fact about whether to cut your string out after ot has snapped or not. But turns out, I was scrolling down the threads and found out that not all of them do. So due to my boredom I'm just gonna answer that question and explain why so that it may help that small fraction of people out there.
Firstly, if your string snaps, immidiately cut it out, espacially if you strung it at a high tension. Why? Because when you string snaps, the area of where it snapped will lose all its tension thus the string bed will have an uneven tension. This will apply different amount of pressure and force to different parts of the frame thus causing it to bend. When to top of the frame bends, it will weaken or even crack the T-Joint. When the T-Joint is loose or cracked, every swing applys greater pressure on it until it eventually breaks of the shaft. And even if your T-Joint does not break off, the string bed will be curved thus your shot will not direct the shuttle straight and is very unpredictable to where it might head to. And thats not all, when your frame is bent it will be weakened and mishits during and hard shot or smash may break the whole racket apart.
It's probably a good idea to talk about how to cut the strings too. In my view, it is always best to cut in a way to minimise the distortion to the frame... i.e. to cut the same string on the opposite side. For example, if I snaped a main, say at B8 I would cut the same main on the opposite side. Then cut the second to last cross at the top before cutting the bottom cross and continue with the rest in the same way. I cut the top cross before the bottom cross because the bottom of the frame (near the T) is stiffer/stronger than the top of the racquet.
One of the coaches at my old club said not to cut the strings as the stringer wont know how to restring it. I never knew I could pull "how the hell did you become a coach?" face.
Facepalm. What about the simple fact that the stringer before did not the default pattern? I cut my strings everytime in training if they breaks. Only at tournaments it do it in the breaks. A good pair of scissors must be close to the court if you use high tension (anything above 28lbs).