Are the Shaf' and Witr prayers and the Dhuhr Sunnah obligatory every day, and what advice is there for someone who feels too lazy to perform them?

The Witr prayer is a confirmed Sunnah. Neglecting it constitutes a deficiency in one's religious practice and warrants blame if persisted in. Imam Ahmad said concerning one who abandons the Witr: "He is a bad man whose testimony should not be accepted." The same applies to the regular supererogatory prayers (Sunan Rawatib); their omission does not make one sinful, but it deprives a person of much good and diminishes their religious observance. Persistently abandoning them out of negligence and aversion may even constitute فسق (transgression). Regular observance of supererogatory prayers compensates for deficiencies in obligatory prayers and earns the servant the love of Allah the Almighty.