MAJORFailure Reference

ByteDance Seedance Motion Drift — Pre-Generation Risk Reference

Technical Classification

Motion Coherence & Tempo Failure

Seedance produces high visual fidelity but motion coherence is its weak point. Prompted "smooth dolly forward" generates a stutter; "slow pan" accelerates non-linearly; "walking" turns into a jerky shuffle. This is a Motion Coherence & Tempo Failure — the model interprets motion direction from prompt but allocates frame budget inconsistently across the temporal axis. Seedance's support process is reachable through ByteDance's in-app support; technical documentation routes faster than complaint-style descriptions.

How to identify this failure

✕Smooth motion prompts produce stutter or pause
✕Motion tempo changes within the clip
✕Subject motion reverses direction mid-clip
✕Camera motion accelerates non-linearly
✕Motion blur misaligned with implied movement

Real generation examples

Prompt used

"Smooth dolly forward into a city street at golden hour"

Failure observed @ 0:02

Camera pauses at 0:02, jumps forward at 0:03, resumes smooth motion — visible cut not in prompt

Prompt used

"Person walking calmly down a hallway"

Failure observed @ 0:01 → 0:03

Walk tempo varies from 1.2x at 0:01 to 0.6x at 0:03; gait inconsistent

Documentation strength

If you need to escalate

MEDIUM-HIGH — Seedance honours motion-failure refunds when the prompt explicitly specified motion behavior. Quote the prompt's motion language in your request.

AVA is a pre-purchase prevention tool, not a post-purchase recovery tool. Platforms generally do not guarantee credit refunds for output-quality failures; goodwill credits are at each platform's discretion. The strength rating reflects how well-formed your support ticket can be, not a promised outcome.

Prevention + documentation steps

01
Score your prompt before you generate
Run your prompt through AVA's pre-flight scoring against the Motion Coherence & Tempo Failure pattern. Green light = generate. Yellow/red = rewrite using the suggested fix before you commit credits.
02
Capture Generation ID + timestamp if it failed anyway
Find the Generation ID in the URL or share link. Note the exact time when the Motion Coherence & Tempo Failure first appears (e.g. "failure first visible at 1.2s"). Timestamped evidence is significantly stronger than a general complaint.
03
Use the correct technical term in your support ticket
Describe this failure as "Motion Coherence & Tempo Failure". This term maps to a recognised internal workflow in the support system and routes the ticket to the right team.
04
Submit via the correct support channel
Runway has no direct email intake. Pro+ plan: open the in-app AI Assistant (help widget bottom-right of app.runwayml.com), describe the failure with the technical term, attach evidence. Free/Standard plan: human support isn't available — your channel is Discord #community-help with @On Call - Moderators.

Frequently asked questions

Will Seedance refund credits for motion failures?

Yes, when the prompt specified motion behavior the output violated. Quote the prompt's motion language ("smooth", "slow pan", "walking calmly"), cite "Motion Coherence Failure", timestamp the failure, attach the PDF audit report.

Why does Seedance produce inconsistent motion?

Seedance allocates per-frame compute aggressively to visual detail. The temporal-coherence module sometimes loses budget when scene complexity is high, causing motion-tempo drift even with explicit motion prompts.

Which Seedance prompts highest-risk for motion failures?

Long-duration motion (>5s), continuous camera moves, multi-subject coordinated motion, fast tempo changes. AVA flags ambiguous motion language in prompts before generation.

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