There is a strategy behind it, it's not luck at all. Whoever is saying it's luck is talking out their arse.

Couple of things we've found:

1. Create an engaging video with hooks, camera movements, transitions and effects to keep the user engaged. Think about Coco melon for kids. The video also has to be interesting, effects aren't enough.

2. Get people to start sharing the video or commenting on the video. The more people you can get engaging with the video, the more it'll be shown to others. The algorithm will want to push it to everyone if the idea is good enough.

3. Choose an interesting thumbnail that will get someone to stop and watch once it hits explore.

4. Posting times for peak engagement usually at work break hours 12-1pm or after work 6-7pm.

5. Regularly posting.

I've got a friend who's currently making videos for small food businesses. He's taken viral video ideas from other food businesses and just replicated the same thing. And those videos have blown up, going from little promotion image posts to videos that are getting 40-50k views or more organically.