You Do Not NEED Squats Or Deadlifts
Some people say that squats and deadlifts are mandatory and you MUST do them no matter what. In reality, exercise selection is very important and dependent on the athlete(you) and your ultimate goals when it comes to lifting. If you are planning on competing in a standard powerlifting meet(squat, bench, dead) then yes, you MUST perform squats and deadlifts. You will need to compete in these lifts and perform a 1RM in those lifts. If you never do squats and deadlifts and have only been doing lunges and leg press, you’re not going to do so hot when it comes down to the meet.
If we are talking about the general population, then no, you do not need to ever perform a squat and deadlift. Again, depending on what your goal is, you can perform a variety of exercises that you can implement instead of the squat and deadlift.
If we are talking about bodybuilding, no you do not need to perform the squat and deadlift. Are they still one of the most comprehensive lifts for overall muscle building? Yes, they are some of the best movements you can implement for overall strength and muscle building. Deadlifts are some if the best lifts for stimulus and progression over time.
If strength is the overall goal, If you play a teamsport, are an endurance athlete, strength training will always help. All sports can benefit from some sort of strength training, does not necessarily mean 1RM strength but for durability, fixing muscle imbalances and even out body parts that get overused in your sport or daily life.
There are no definite in sports or the gym. There are always work arounds if you need them. There are so many exercises and lifts that can be used and applied at different times to help best suit a person or athlete for whatever their goals may be. This is where a good strength and conditioning coach comes in and helps analyze and provide these suggestions for exercises that best fit your body and your goals.
So overall, squats and deadlifts are NOT necessary depending on what you plan to be doing. They are one of quite a few great exercises that can be used in a variety of situation but they are not a mandatory lift.