I usually do when I get enough pokemon to start forming a basic strategy for my party. The only exceptions are Pikachu from Yellow, and whenever I pick the water starter. I usually turn the water starter into a HM slave. They do get to enjoy the sunlight for a little bit since I usually try to evolve most of my pokemon to their final form. --- "Wherever they burn books they will also, in the end, burn human beings." Heinrich Heine AKA Couchpotatodx
I did with my grass starter in Black 2. I swapped it out for Keldeo when the starters usefulness was outlived. I just now brought it back out, post-E4, to have it evolve to its final form. --- Not changing this until Capcom either gets their act together or the company goes under (Dragon's Dogma was a good start.)
Once, in my current I boxed Serperior. For some reason I expected him to be better this time than the first time I chose him and restarted the game because he was crap. --- "How the Christ do you expect to reverse-Atlantis an entire city? You're just the Dragonborn, not the Daedric Prince of Civil Engineering." - DocWily
Sometimes, particularly when I am doing a run with Pikachu as my lead (just something I do for fun on occasion since Pikachu is my favourite). --- We shall rise again to start anew. White FC: 0862-2660-4156 / 3DS FC: 2492-4470-1418 / White 2 FC: 4556-7836-2644
I boxed my Pikachu on a playthrough of Yellow once....... yeah.
Thing is, Pikachu was never my headliner in that game. For some reason I'd always catch and train a Pidgey. Pidgeot was my headliner then, way back. --- Official Sabin and Layle of the Dissidia 012: Duodecim Final Fantasy Board.
Only on SoulSilver because I hate gen 2 and on my newest Emerald ROM playthrough, because I'm hacking to get whatever I want whenever I want. --- I don't care what you say, Generation II sucks. That's just my opinion, no matter how true it may be.