Your zones are watered multiple times a day, you probably selected clay, clay loam or loam as the soil type which accepts water slowly, often as little as 1/4 inch per hour and that is why we break the watering into many pieces to avoid water runoff.
For your zone 4, the watering duration is about one hour because you selected shrubs as your plant type. Shrubs require deeper watering with less frequency because they have longer roots and can absorb moisture from deeper soil, while annual flowers and grass needs to be watered more frequently.
We just noticed you have disabled the smart zone feature so the rain delay feature will also be disabled. If you still want to use smart watering and water zone 4 more frequently, you can set it via settings -> zones -> SmartZone -> Mode -> Frequent.
If you still need the rain delay feature and do not want smart zone schedule to override your own programmed schedule, you can set up the Smart Zone level from Advanced to Basic, which only skip rainning days for your programmed schedule.(Settings->Zones->Smart Zone)
For more information about Netro smart watering, here is an article about Netro three watering modes which might be helpful. https://netrohome.com/forum/posts/111