Before I answer this question, I want to think about the problem that Facebook Groups is solving for its users and the value it offers. Facebook Groups enables people to create communities in the virtual world. And people in a community usually gather together because they share something, whether that’s a cause, sickness, neighborhood, or something else.

There are different metrics that can represent the usage of Facebook groups. I’ve listed a few here:
# of Facebook groups per user
# of meaningful comments / likes per day per Facebook Group
# of users per Facebook Group
And many other ones.

Out of the KPI’s listed above, I’d like to focus on #2 because I think it’s more meaningful than others.

When I think about a Facebook Group user, I consider some of the concerns they might have in commenting or liking a post. One of the concerns can be privacy. They might be concerned that they don’t want to broadcast their ‘comment’ or ‘like’ to everyone in their Facebook Group. Instead, they’d like to share their reaction with only the members of the Facebook Group.

One feature to address this problem could be ability for user to easily chose whether or not their like / comment will appear in newsfeeds. It’s possible for the users to go to their Facebook Profile today and remove a post from newsfeed but many users are not be aware of this functionality. You can remove user anxiety a lot more if you could enable the user to limit the audience of their reaction to the Facebook Group right from the start.

To implement this feature, I would add a little icon on the right left side of the section that shows comments and likes and present the audience. If it’s Facebook logo, it will be Facebook Newsfeed. If it’s the Group logo, it will be just people in the group. User has the option to chose the audience before even submitting their reaction. In the future, you can add more audience groups (e.g. family, close friends, etc) as well. This will allow the person to quickly chose who sees their reaction, making them feel more comfortable with expressing themselves in front of the right audience. And as they get more comfortable with expressing themselves, the number of comments and likes in Facebook Groups will increase.

Here’s a framework for improving usage type of problems

1. Clarify functionality of feature
2. Clarify the phrase “improve usage”
3. Identify Metrics
4. Map user journey
5. Identify Persona
6. Identify use cases & pain points
7. Identify Solutions
8. Prioritize solutions
9. Design
10. Validate
11. Iterate
12. Launch & Measure

1. Clarify functionality of feature
2. Clarify the phrase “improve usage”
Let’s say a discussion with the interviewer reveals that “improve usage” really just meant that we want to “increase number of social groups”

Then, let’s assume we have the following current metrics:
a) Active group posts = 100MM each day
b) Active comments = 200MM each day
c) Active reactions = 300MM each day
d) Active Shares = 450MM each day
d) Total groups = 1MM

3. Identify Metrics
Let’s say we identify that we want to “increase number of social groups” , so that communities could stay more connected.

4. Map user journey
GROUP ADMIN:
> Group admin decides to create a new group
> Group admin sends an invite to others
> Users start following/joining that group
> User is interested in the group

5. Identify Persona
Jane – 28 yrs old – interested in starting group about women’s health – Yoga & nutritionist specialist

6. Identify use cases & pain points
> Discovering existing groups
> Targeting local neighborhoods for groups of interest
> Users seem to drop off during group creation steps –
> Users are unable to find the button to create group

7. Identify Solutions
> Prompt people to start groups based on personal interests
> Simplify group creation process
> Free advertise new groups created to community of target users

8. Prioritize solutions 
a> Simplify group creation process & discovery — Low Cost, 2 man months – 10% improvement
b> Prompt people to start groups based on personal interests — Medium Cost, 6 man months – 10% improvement
c> Free advertise new groups created to community of target users — Medium Cost, 4 man months – 5% improvement

9. Design
~ Create some designs

10. Validate
~ Validate with target customer, before building the full implementation

11. Iterate
~ Keep repeating until you find the right designs

12. Launch & Measure 
~ Keep on tracking the key metrics
~ Launch to a smaller segment of new users & measure impact
~ Then slowly increase to larger segment of users.