The showrunner said that he wanted the conclusion of the CW series to satisfy viewers by "acknowledging their allegiance".
"The finale feels nostalgic in the right way and works best for the people who have loved the show and know the history of the show," he told TV Guide.
"I wanted it to be a bit of a reward to our core fans who have been so faithful to it and I wanted them to feel like we were acknowledging their allegiance to the show over the years."
Schwahn said he was proud of the success achieved by One Tree Hill in spite of a lack of support in its early years, describing it as the "little show that could".
He stated: "We didn't get a lot of support, we got zero critical acclaim and we rallied around that; it became a badge of honour to us [like] a secret little club.
"There are things certainly I would change, but when you get this far and considering we've all gotten along and enjoyed it, you've done a lot more right than wrong and we should be proud of that."
One Tree Hill's final episode airs in the US tonight (April 4) at 8/7c on The CW. The season is currently airing in the UK Mondays at 9pm on E4.
> 'One Tree Hill' exec 'not holding back for final season'
> More One Tree Hill coverage