PS Vita could've been a hit had Sony taken a few key steps.
1.) No Proprietary Memory Cards - This was unnecessary, and showed that Sony learned nothing from UMD and Memory Stick. Micro SD would've been a better alternative.
2.) If you had to use them, then don't price them way above standard - $20 for 4GB is laughable. These Cards really should've been $5-20 MAX.
3.) Market the damn thing - Even at launch, the Vita had barely any advertising. They should've ran a substantial ad campaign that demonstrated the console's unique capabilities, not put out 2 commercials and that's it.
4.) Get better third party games - Banking your system's future on a Crappy CoD spin-off instead of some decent exclusives or ports is laughable. Try to get better deals with third parties, and make sure to get the right games the PS Vita needed.
5.) Invest in more first party games - I get that Naughty Dog and the like aren't interested in developing for underpowered handhelds. But You should've found more developers who would support the Vita using PlayStation IP, and get some of your lower tier developers to make more games for it. Games like Gravity Rush and Tearaway should've been way more common than they ended up being.
6.) Don't compete with smartphones - Instead focus on what makes the Vita unique compared to smartphone gaming. Switch has shown that both types of systems can co-exist, so Vita could've done the same.
This is all what the Vita needed to have a better chance in the market.
4) It was too good. I know that sounds strange but hear me out. The graphics were on next gen levels meaning development required more time and finances which was a risky thing for developers because of the weak sales caused by the abovementioned points. This led to a platform with few games at PS3/360 price-ranges which held gamers back to invest in the handheld. This again led to developers not wanting to take the risk and make games for a weak selling platform which led then again to fewer buyers. Eventually the poor handheld fell into a downward spiral leading to its inevitable demise.
Yeah, I don't really buy that. Vita was much weaker than the PS3 and 360, and the games that were expensive to make were simply developers trying to bite off more than they could chew. IMO, the Vita simply needed more games built from the ground up for it. Ports of console games are fine, but not when the system doesn't have any exclusives to help drive sales and make it worth it. This is yet another thing the Switch got right over the Vita. It had a strong lineup of First party games and exclusives right out of the gate, thus driving up software and hardware sales making publishers confident in porting games to it.