New Pramac Ducati recruit Scott Redding admits he questioned his future in MotoGP during a "demoralising" two first seasons in the premier class.
After finishing second in Moto2 in 2013, the British rider was 12th in his rookie campaign on an Open-specification Honda run by the Gresini team.
He returned to Marc VDS - his Moto2 outfit - last year and was 13th on a works-specification Honda.
When asked how he would summarise his first two seasons in MotoGP, Redding told Autosport: "Really f**king shit, if I'm honest.
"My first year with the Open bike, the results for the bike were not bad, but the problem is that the results are not results.
"Finishing 12th and 13th, in my head, that's not a result, and that's a bit demoralising, knowing that I could never actually win a race.
"The second year was the same scenario, just that the bike for me wasn't working. I just lost confidence.
"We tried everything and I lost belief in myself.
"I thought, 'you know what, I've lost the touch in racing, I haven't got it to be in MotoGP'.
"It was demoralising me mentally."
Redding claimed his maiden podium at Misano last year, finishing third in the wet-dry race, but he admits that did little to help.
"That podium was a bit strange," he said.
"It didn't really feel like a podium, there was a lot of politics going on with me and the team.
"It didn't really feel like racing that weekend, which is a bit annoying really, because it could have been a nice race.
"You've got to do what you've got to do, no matter what goes on off the track you always give 110 per cent on the track in the race.
"For the situation and conditions, I do believe I deserved that podium.
"In general, it wasn't happening. You try and you try and you try, and you don't get anywhere."
Redding was in the top 10 throughout last week's test at Sepang as he began his first season racing for Ducati.