Sometimes we take all the right steps, and still end up failing. And that holds true when it comes to the wonderful world of innovation and invention.
Once I worked on a product where the prospective client asked for the impossible. We huddled together and used every engineering trick we could think of. In the end, we created something that had such stellar performance no one believed us. By the time first units were sold, the competitors have caught up.
Although that was disheartening, I used the opportunity to reflect, and think deeply about what happened. In the process I realised that I have to step out of my engineering "bubble" and really understand other parts of business as well—from marketing to sales to negotiating, and so on.
If you wish to succeed with innovation you must have the tenacity required to survive the inevitable failures that await you. Don't dwell on them—reflect on what happened, extract your learning from it, and move on.
Do the best work you can, and meet the future with no regrets.