manasib

Bond prices converge to par at maturity, because at maturity, the only payment is the final coupon and the par value. So, if you think of it in terms of a PV of a lump sum, it should make sense.

If coupon rate = market rate (i.e. the YTM), price = par. If coupon not equal to par, but the market rate stays constant, the price will converge monotonically to par (i.e. it will get closer to par each and every period). However, if the market rate changes, the convergence won;t be monotonic.