OTT trailers vs theatrical trailers: what changes
On a streaming platform, your trailer competes with the next thumbnail, not the next film in the multiplex.

A theatrical trailer is watched by an audience that has already chosen to be in a cinema. An OTT trailer often autoplays on a home screen, muted, while the viewer is still deciding what to watch tonight.
The first seconds decide everything
On OTT, the opening seconds carry most of the weight. The hook has to arrive fast, and it has to work without sound, since many previews play muted.
Artwork has to work in rows
Platform artwork sits in rows next to dozens of other titles, often cropped into different shapes. Key art for OTT needs versions that hold up as a wide banner, a vertical tile and a small thumbnail.
Different deliverables, strict specs
Streaming platforms have detailed technical requirements for trailers, artwork, subtitles and metadata. Getting these right the first time avoids delays in going live.
Same film, new audience
A film that already ran in theatres can find a second life on OTT with a fresh trailer cut for viewers who missed it, focusing on what the home audience will enjoy most.
In theatres you win the audience once. On OTT you win them every time they scroll.