You don't ask for a raise when business is not going well or when things are tense around the office. You don't try to correct someone who feels threatened by you. You don't ask for a favor when someone is under a lot of stress or angry. Timing is important in cooking. The juicy hamburger on the grill is raw meat if cooked for too little time and a clump of charcoal if it is cooked too long.
Timing is important in medicine.
If you catch a problem early you will be able to treat it more effectively. You timing is important in taking medication. If you take your medicine as directed it will be helpful. If you skip doses it loses it's effectiveness. If you take extra doses it can be deadly.