Real work is rarely a flat, unordered list of tasks. It has structure: tasks break down into smaller pieces, and some tasks depend on others. Sub-tasks and dependencies capture that. This piece is about them in Odoo Project.
Sub-tasks: breaking work down
A task may be large enough that it is genuinely made up of smaller pieces of work. A sub-task is one of those smaller pieces: a task broken down into its component tasks. Sub-tasks let the structure of work be captured, a larger task and the smaller tasks it consists of, rather than everything being a flat list. In Odoo Project, sub-tasks let a team break a task down into its parts, which makes large pieces of work manageable, each part a task in its own right, while the relationship to the larger task it belongs to is kept.
Why breaking work down helps
Breaking work down into sub-tasks helps because a large, undifferentiated task is hard to manage, and a large task broken into its real parts is manageable. Each sub-task is a smaller, clearer piece of work that can be owned, tracked, and got done, and the progress of the larger task is the progress of its sub-tasks. Sub-tasks turn a daunting large task into a structured set of manageable pieces, which is how large work genuinely gets done.
Task dependencies: the ordering of work
The other kind of structure in work is ordering: some tasks genuinely depend on others. A task may not be able to start until another is done, because the second genuinely needs the first. A task dependency captures that: it records that one task depends on another, that there is a genuine order between them. In Odoo Project, task dependencies let the genuine ordering of work be captured, so the project reflects not just what tasks there are but the order they genuinely have to happen in.
Why dependencies matter
Task dependencies matter because work that has a genuine order has to be done in that order, and if the order is not captured, it can be got wrong, a task started before the task it depends on is done, which does not work. Capturing dependencies means the genuine order is part of the project: it is clear which tasks are waiting on others, and the work can be done in the order it genuinely has to be. Dependencies also make planning realistic, because the order of work shapes how a project genuinely flows. A project with its dependencies captured reflects the real structure of the work; one without them is a flat list that ignores the genuine ordering.
Capture the genuine structure, not more
An honest note. Sub-tasks and dependencies capture the genuine structure of work, and they should be used to capture the structure that genuinely exists, not to impose structure that does not. Break a task into sub-tasks where it genuinely consists of smaller pieces; capture a dependency where one task genuinely depends on another. Over-structuring, breaking down what does not need breaking down, recording dependencies that are not real, adds fiddliness without reflecting reality. The aim is a project that captures the genuine structure of the work, its real breakdown and its real ordering, no more.
The takeaway
Sub-tasks and task dependencies in Odoo Project capture the structure of work. Sub-tasks break a large task down into its smaller component tasks, which makes large work manageable. Task dependencies capture the genuine ordering, recording that one task depends on another, so work is done in the order it genuinely has to be and planning is realistic. Use them to capture the genuine structure of the work, its real breakdown and real ordering, not to impose structure that does not exist. For how we approach Odoo, see our ERP practice.