Product development projects are not just about the finished product. Getting to market in a timely manner is what matters most, so it's important to have systems in place for all stages of the project, including how you track action items, issues and potential problems that arise.
The Daily Log helps with this because it can help supplement your other planning documents, in case they are lacking some information or if some situations aren't specifically covered by a particular report.
A Daily Log can come in handy when your project includes a lot of moving parts. It's best to use the Daily Log when you have at least one action item or issue each day, so that it doesn't get too overwhelming or difficult to manage.
If we look at the majority of product development projects, these usually have a lot of moving parts. It's best to start using the Daily Log from day one, so that you can build up a solid record for future reference instead of scrambling at the last minute with no clue what has been going on with your project so far.
In short, anything that's not already documented goes into the Daily Log.
Whatever actions or issues arise, it's important to capture them in the Daily Log. It can be used as a place to summarise information for your team but also as a place to record action items so you don't forget about them.
As long as it's relevant and helps with Project Management, you can record anything you want in your Daily Log. It's essentially a free space to log whatever is on your mind so it doesn't get missed or forgotten amongst everything else that needs to be done.
Your Daily Log is most useful when you're consistently updating it each day.
It's also best to make the Daily Log accessible for all members of your project team instead of having one person update it. This way, everyone can contribute and make sure that nothing slips through the cracks.
The most effective way to use a daily log is to make it a daily task. Although not everyone has time to fill out the Daily Log every single day, if you make an effort to do it consistently then there's less of a chance that important information will be left out or forgotten about.