two examples to help understand recur and loop....recur

recur.clj

(defn count-down [n]
  (do 
    (println "Method Started")
    (println "Number : " n)
    (when (pos? n) (recur (dec n)))))

;; when you run (count-down 5), output is
;;  Method Started
;;  Number : 5
;;  Method Started
;;  Number : 4
;; ... so on ....

;;loop-recur
(defn count-down [n]
  (do
    (println "Method Started")
    (loop [a n]
        (println "Number : " a)
        (when (pos? a) (recur (dec a))))))
;; (count-down 5000) will print method started only once.