I cannot explain intuition because intuition means arriving at the correct answer without knowing why.
I can, however, give you a simple example that will spur your understanding (which, frankly, is a lot better than intuition).
Suppose that the 1-year spot rate today, s1,0, is 1% and the 2-year spot rate today, s2,0, is 2%. (I’m using the “,0” in the subscript to emphasize that this is a spot rate when we’re at time t = 0. In a moment we’ll need the 1-year spot rate when we’re at time t = 1, and I don’t want y’all to confuse the two.) Then the 1-year forward rate starting one year from today, 1f1, is calculated as:
(1 + s1,0)(1 + 1f1) = (1 + s2,0)2
(1 + 1f1) = (1 + s2,0)2 / (1 + s1,0)
1f1 = (1 + s2,0)2 / (1 + s1,0) − 1 = 1.022 / 1.01 − 1 = 3.0099%
Let’s say that you have a 2-year, annual-pay, $1,000 par bond with a 3% coupon rate. The value today is:
V0 = $30 / (1 + s1,0) + $1,030 / (1 + s1,0)(1 + 1f1) = $30 / 1.01 + $1,030 / (1.01)(1.030099)
= [$30 + $1,030 / 1.030099] / 1.01
In one year, the value (including the coupon payment you just received) will be:
V1 = $30 + $1,030 / (1 + s1,1)
If interest rates evolve according to the forward curve, then s1,1 = 1f1 =3.0099%, so,
V1 = $30 + $1,030 / 1.03009
So,
V1 / V0 = [$30 + $1,030 / 1.03009] / {[$30 + $1,030 / 1.030099] / 1.01}
= {[$30 + $1,030 / 1.03009] / [$30 + $1,030 / 1.03009]} × 1.01
= 1.01
= 1 + s1,0
For bonds with more than 2 periods till maturity, the same sort of thing happens.