The longer the VEG cycle, the more the yield.
Consider this, in nature, outdoors, we plant a seed in mid to late April. It grows through April, May, June, July, and in mid to late July, as the sun's rays change, the plant naturally changes from VEG to FLOWER, with the diminishing sun's rays. That is nature's way. The plant grows and matures to an adult plant for about 3 to 4 months. THEN, it makes flowers. That is nature's way.
Indoors, in HYDRO with feeder tubes, we cut that time in half, by using 24/7 LIGHT. instead of 3 months, or 13 weeks, it takes about 5 to 6 weeks to become a mature plant in HYDRO, with 24/7 LIGHT. Pot plants growing as young plants, make what we call nodes, or a set of two leaves, one directly across form the other. When a pot plant is mature, it will make new leaves one at a time, not directly across from an other leaf, but staggered.
OK, also in nature, in addition to plants, we see animals and humans reproduce at maturity or adulthood. If a human, (or dog or any animal) is forced to make babies before maturity, like getting a 12 yr old girl pregnant, or a dog in her very first heat, then the babies are weak, or runts, or deformed, and just not at their best.
A dude here, a most experienced, knowledgable grower named fdd2blk (and a MOD here too) taught me a long time ago, that it does not make sense, it is not wise, it is not logical, to make a child have a child, and it is not wise or smart or logical to make an immature baby plant, have babies. LET THE BABIES GROW AND LET THE ADULTS MAKE BABIES.
If you will VEG for 5 weeks, to 6 weeks, you will have more time for proper TOPPING, PRUNING, AND FIMMING, and you'll get bigger plants, a much larger yield, and you will also have a mature adult plant, ready to make healthy, stronger babies (flowers) .
If you begin Indica Flowering, after VEGGING 3 or 4 weeks, you will harvest about 60% to 75% of what you would have harvested, IF you had waited and VEGGED for 5 or 6 full weeks.
This info applies to rapid growing in Hydro, and to Indica strains. NOT slowly in SOIL, and NOT Sativa.
I average 3 to 4 ounces per plant, VEGGING 5 to 6 weeks, and I have gotten 7 ounces from one plant