# Review Wait Time

![Review Wait Time graph](https://cdn.prod.website-files.com/610c8a14b4df1ae46b1a13a3/634800eb3c45b5629e3e4219_Review%20Wait%20Time.jpg)

**What it is:** This shows how long people wait to get feedback on their PRs.

**Why it matters:** This is one possible bottleneck for `Change Lead Time`. When people have to wait longer for feedback, it can mess up their workflow. They’re more likely to start a new piece of work while waiting for feedback. When they get that feedback, they have to context-switch, making it harder for them to remember what they did. This often results in longer times taken for each of the tasks to be completed (for example, [one study showed](http://blog.ninlabs.com/2013/01/programmer-interrupted/) that it takes 10-15 minutes to get back into context).

Moreover, there’s bias in how long different groups of people have to wait for feedback. For example, [this research](http://www.erinhengel.com/research/publishing_female.pdf) showed that women had to wait longer than men for feedback. This is why we *do* show this metric at the individual level — so that you can make sure that everyone is receiving feedback in a timely manner.

**How we calculate it:** We measure the **number of hours from PR creation until the PR gets feedback**. This could be a comment, review, or merge by someone other than the PR author. It excludes time that the PR spends in a draft state, since the draft state indicates that the PR author is still finishing the work. To be clear on some nuances:

* `Review Wait Time` is `null` if the PR has no feedback. It ignores responses from bots and responses that came in after the merge (since we exclude selfie merges).
* See [here](https://docs.multitudes.com/metrics-and-definitions/process-metrics/change-lead-time#additional-calculation-notes-for-change-lead-time-and-subsets) for some additional calculation notes that apply from `Change Lead Time`.

{% hint style="success" %}
**What good looks like**

We recommend that `Review Wait Time` be under **4 hours**. This threshold is based on an internal analysis conducted by Multitudes across 80,000 PRs from a diverse range of customers and comparing against the SPACE and DORA research.
{% endhint %}