No. Annuals require a different management methodology. It is sometimes preferable to treat perennial vegetable crops this way - not picking asparagus for the first two years, or cutting the flowering stalks off of garlic or tulips, but sacrificing beans will gain no advantage. Beans should be continuously harvested; that will prolong their output. Once beans (and many other veggies) start to ripen, production stops, which is why it is important to pick thoroughly. You have to consider that the primary impetus of the plant is to survive and reproduce, so once seeds are produced, its' "work" is done for the year. Removing the seed potential from garlic causes it to try to reproduce via the bulb, resulting in larger cloves. Removing fruit or flowers from trees causes them to put down deeper and wider root systems, helping to ensure better cold weather survival. With most vegetable crops, you are best off taking what you get as soon as you get it, because you never know what might beset your plants as the season progresses.