Subtitled episodes appear internationally within hours of broadcast while dubbed versions follow weeks or months later. The gap is a production sequencing problem rather than a matter of priority.
Subtitles can begin before the episode is finished
Translation works from a script, which exists long before animation is complete. A subtitle file can be drafted, checked and timed against a near-final picture.
The final step is synchronising text to a locked video, which is fast and requires a small team.
Because so much of the work happens in parallel with production, a subtitled release can be ready almost as soon as the episode is. Simulcasting depends entirely on that overlap being possible.
Dubbing cannot start until picture is locked
Voice performance is recorded against finished animation, because timing, expression and mouth movement all have to match what is on screen.
Any change to the picture invalidates recorded lines, so studios wait until the episode cannot change before booking sessions.
That single dependency accounts for most of the delay. The dubbing process cannot begin at the point where subtitling is already finishing.
The script has to be rewritten, not just translated
A dub script must convey meaning while fitting the number of syllables and the mouth positions of the original animation.
That is a rewriting task with hard constraints, and it takes considerably longer than producing a subtitle line that is only bound by reading speed.
Adaptation writers also handle jokes, idioms and honorifics that subtitles can leave visible, since a subtitle reader is watching a foreign-language performance and a dub listener is not.
Casting and scheduling introduce their own delay
Performers are booked into studio time, and a series with a large cast requires many sessions coordinated around individual availability.
Recording is directed line by line, with retakes, which is slow by design because the performance has to sit inside fixed timing.
Mixing follows, replacing dialogue within the original soundtrack, which requires separated music and effects that must be supplied by the original production.
Simultaneous dubs are possible and expensive
Some high-profile series now dub close to broadcast, which requires early access to near-final episodes and dedicated capacity held in reserve.
That access is a commercial concession from the production side and it carries real risk, since late changes waste completed recording.
The cost is only justified where a title is large enough that the dub audience is worth protecting week by week rather than serving later. For most series the economics still favour waiting until the season is complete.