Before Black can be sure he can sac his Rook on move 1, he needs to anticipate these moves:
4. Kd2...Qd4+
5. Ke2...Ra2+
But for 5...Ra2+ to exist, the c2 Pawn can't be there.
To be sure c2P is gone, Black removes it! But how?

So it all comes back to move number 1...R×b3+!
2. c×b3 (removes c2P)...Q×a2+
(Note: if 2. a×b3...Qa1#)
3. Kc1 (forced)...Qa1+
(see 4 & 5, above ~ if 4. Kc2...Ra2+, 5. Kd3...Qd4#)
6. Qc2 (desperation)...R×c2+
7. Rd2 (desperation)...R×d2+
8. Kf3 (if Kf1...Q×f2#)...Qf4#

Is that a lot to anticipate?
It's a lot to recognize, even in retrospect!
Chess Masters do that constantly.