Researching and scheduling your Pins takes the guesswork out and gives you time to breathe. Pinterest only works well when your Pins are being seen by your ideal audience, so using a scheduler to send your Pins out at the optimal time will save a lot of hard work and heartache.
A good scheduler will know when your ideal audience is on Pinterest. Your content will go out into the Pinterest world and will have a better chance of being seen by your ideal audience.
Manually Pinning is fine, but Pinterest does frown upon Pinning madly in a short time. It’s considered spamming in the eyes of Pinterest and you risk having your account shut down. So, this is another good reason to use a scheduler.