The cons of X-plant

First, i'm not a farmer, nor am i even a gardner.
That being said, i am a hobbiest who enjoys the fruits of his labor.
I grow very modest amounts of Gods gift from the earth. 2 plants is max for me. I've only been at it 8 months or so.
So for dirt heads like me who grow small amounts, the question is.
I see lots of pics of seedlings in cups, bottles, ect.
For the small i.e. closet grower, why not just skip the cup/x-plant and go into your final pot.
In my case i start germinated seeds in 2 gallon pots filled to the brim, as the soil settles after time, and i can just add some fresh soil later in her life.
The only drawback i see is wasting soil if seeds don't germinate. I myself would rather eat the soil cost than shock young seedlings, or older vegging plants by transplanting.
As i said, im pretty new to growing so any thoughts are welcome.
Peace

You will get different answers.

Some people like to x-plant a few times.

I've read to x-plant once. I follow that but add a slight twist Start in 1 gal grow bags, then into 4 gal buckets. I cut off the bottom of the bags and place on top.

Too small pots/cups at first I find more a prob watching the moisture. Small pots dry out faster.

Starting in a big pot, might give the look of a stunted plant as the plants root go nuts growing, pausing the top. Don't sweat it, they will even up.

I have read that if you allow a plant to grow into a pot until it is at about the max it can grow ( not root bound, but if you pulled it out and looked you would see a lot of roots) and then transplant it, Can cause explosive growth. Now I cant recall where I read this, but I know I did. A second plus I can think of is that it sure is easy to toss around gallon grow bags all day, but try doing that with big pots...especially when the plant in it is two inches tall. Oh and you can more efficiently use the space below your light. Either way you can grow some pretty amazing plants...GL
SP

Yeah im sure people have alot of reasons for doing it. Personally i start in small pots because my veg cabinet is way smaller than me flower area so i have to conserve on space