Timbaland gets bored with new artists he signs very easily. If they don't have that instant fame he drops them. He's used to working with major pop stars that give him major ratings, press, ect. He tries to go back to his R&B Hip Hop roots because I really believe it's the music he loves making the most but it just doesn't have the same effect in the grand scheme of the music BUSINESS. Tink is talented, but R&B is a dying art form unless you're doing the trap soul style stuff Tiller & PnD are doing and those lanes are already locked down by those two. It's real hard for a female in the music business especially in R&B because it's driven by men singing love songs to women.
Tim has broken more Hip Hop and R&B acts than he has Pop acts. With Pop, he's saved careers (Nelly Furtado) or he helped legitimize them as solo acts (Justin Timberlake). He's never had a Missy Elliott or Ginuwine in Pop where he entirely produced a debut album and it took off. So Tink is an artist that should've been a no brainer.
IMO, what stopped Tink from blowing up is three things:
1) Music that wasn't exceptional
2) Timbaland's ego and arrogance. This plays off point #1. He put out records that sounded like Timbaland songs and not Tink's. That wasn't her sound and was a departure from her base. On top of that, he kept comparing her to Aaliyah and Lauryn Hill instead of allowing the people to make comparisons. He should've stayed a silent co-sign like he did with Bryson Tiller. He managed to give Bryson Tiller two bangers and one of them charted without Timbaland ever going overboard with promo and comparisons.
3) Movin' Bass. This is perhaps the biggest misfire. Ross and Tim dropped the ball with this because the fans were cheated out of dope record. Jay Z's verses were cut from the song and the one on Ross's album is completely stripped down. That's really neither here or there. If Timbaland had waited to drop this after Ross dropped the video for the song and gotten permission from Ross, Tink's version might've taken her further.