And good deed has both reward and barakah+noor. Different places, or different times (eg Ramadhaan), means different reward and barakah. Noor of Dhikr stays with you and keeps you away from sin. Hence we do it in the morning - whole day different. Noor will multiply and come with you in grave, help you, also help you on judgement day, with glowing faces and thrones. Do morning, evening, all the time.
