Question about pot size??

Hey I was just wondering if anyone had an answer to this question, it seems to kinda baffle anyone i ask. Whats the purpose of switching pot sizes throughout a grow? like going from red cup to a 1 gallon, to a 3, then a 5. why not just put it straight to a 5 or 7 whatever you plan on using to flower? i just was wondering because when a plant is in the ground it has no limitations so why transplant so many times? any answers are appreciated thanks in advance.

I dont do a bunch of transplants, but I do go into cups for the first few weeks of vegging.

I do it for space. I can veg a lot more plants in a smaller area in cups for the first few weeks. (Currently limited to a tent for vegging due to room rearranging)
Cuts down on the # of lights I need in veg, which saves me power.

I then transplant to my final container for the remainder of the grow.

wen ther young plants its easier to control feeding and stuf wen in a small pot,and as the plant gets bigger u increase pot size,sum people like to let the plant get a little rootbound before changing pots to gt better growth,thers lots of reasons but its a common practice and works so stik to it

to get a good, solid root ball going, and to stimulate growth. plant a seed in a 5 gal container, and then transplant up via 3 transplants, to that 5gal container. see the difference.

It would be a bitch to start seedlings in 3 or 5 gallon containers. The plant would be lacking a root system, it would be difficult to water properly. If you're starting regular seeds and you have to sex them it would be such a waste of resources and soil.

Along with the reasons others already mentioned; logistically you can start more young plants under one light in smaller containers, they're much easier to move around and maintain, and transplanting makes for a more robust root system.

I would say the hard thing I learned was from going 3gal pot to a 15 gal pot...Not the best idea. Instead of being able to water every 3 days,it would take 5-7 days before the medium would dry up to water again...If you transplant a few times you can build up your roots and not risk drowning your roots which can lead to unhealthy plants and root rot. Plus,you have so much more control over your girls.

A lot of people do start in the final pot and do well. I veg them in a beer cup for space reasons, also for less soil used. If I had all female plants I would just put them in their final pot.

I like transplanting, you get to know your plants right down to the roots. I got my first good smell from them yesterday when i transplanted. I held them horizontally to loosen up the plant and POOF aroma