Some people find this Pokemon absolutely terrifying, while some older trainers get flashbacks to The Magic Garden, which was a late '70s/early '80s children's program hosted by two hippies and clearly influenced by hallucinogenic drugs (it had a pink squirrel and a giggling flower patch!). Anyway, this Pokemon looks like a doodle of a flower with a mischievous grin drawn on it with magic marker - not exactly the most creative Pokemon we've ever seen.
Above: Wipe that smile off of your face Sunflora. You suck
As a battler, Sunflora has a great Special Attack stat and woeful Speed, accompanied by other unimpressive stats. As a Grass type, its move pool is predictable and a bit limited. At best, it can work as a Leech Seed staller or a Sunny Day recipient, but there are way too many Pokemon that outclass it. Venusaur, Meganium, Cherrim, and Jumpluff are just a few that come to mind. At the end of the day, we have no idea what Sunflora is smiling about - it's a pretty sorry excuse of a Pokemon.
Even legendary Pokemon can be kind of meh. Take Entei for example. Perhaps we're biased due to the crap Pokemon movie it starred in, but we hate how this Pokemon looks. First of all, it's part of the trio of legendary cats, but it looks like a dog. Actually, it looks like a dog that ran through the closet of a cosplayer. Seriously, it might as well be a mask-wearing mutt with garbage glued onto its back.