Most fights are over in seconds
Most fights end quickly. Often, the loser will be decided in the first few seconds, the victim of the first good blow. If most fights only last a few seconds, how many techniques do you need to know? Knowing numerous techniques is not only unnecessary but dangerous. For a technique to be useful, the user needs to be able to apply the technique with little or no conscious thought. If the user has to choose from numerous techniques, he or she must not choose the wrong one. Instead of learning numerous techniques, learn the basic principles of self-defense and then react to your opponents movements with techniques that cause them pain.
Blocking and countering is unlikely to work
Blocking works best at long range, as in sparring, and it works best when you can see the attacking technique coming. Neither of these things is likely to occur in a close range fight. Watch boxers, how many blocks do you see them do. If the attacker is intoxicated and moving in slow motion, you may be able to block, otherwise, you must learn to slip attacks and counter hard and fast.