They are always bad shots
Some of them you can feel them straight as you click the shutter. Some others you will think are good and will notice your framing is not perfect. Light was wrong. Overexposed, underexposed. Not in focus. So many things could go wrong because of technical matters. they are always bad shots.
The more your practice your craft, the better you get a it and the less trash you leave behind you. Look at Kobe Bryant, the Los Angeles Laker’s basket Ball player, he was coming everyday at 05:00 to the gym to put 400 shots before starting his day. Be the Kobe Bryant of street photography.
Don’t delete your photos on location
Don’t do that. Some of them are obviously bad and you know it, but you need to calculate your success/failure ratio and removing samples is not in your interest to see the improvement of this figure. Everything you monitor, get’s better.
Failure is totally fine. As long as you are happy to accept it as a step forward. Failure is learning unless you are not willing to learn from your mistakes. Take notes, create a folder on your computer with the failed pictures. Seriously, store them in a folder and look at them in a few years, analyse them and take notes of why you consider them as failures. You can also ask for advises of photography peers (and not your family or friends) and listen to their feedbacks.
If you apply yourself at keeping records of your failures, at learning from your mistakes and keep on shooting: you will succeed. Your photos will get better and better, less failures and you’ll be more and more confident. You will refine your style and: you will succeed.