Why would someone, healthy and 10-39 years old, infected with covid-19 might die?

From https://ourworldindata.org/coronavirus we can see that a person between 10 and 39 years old has a probability of 0.2% of dying, which is very low but meaningful.

See also this table below for reference of deaths among healthy and unhealthy people

Why would that happen, what could possibly go wrong?

For example, can weight issues (below or above the average) affect this result?

My question is

• Why would someone, healthy and 10-39 years old, infected with covid-19 might die?
• This chart does not necessarily show that any young and healthy people have died. We don't have a lot of information yet. Mar 16, 2020 at 21:46
• @BryanKrause why did they write 0.2% then ? Mar 16, 2020 at 22:38
• Do you think 100% of people 10-39 are healthy? Mar 16, 2020 at 22:41
• @BryanKrause nop. But hang on, I saw in another table where it said that 0.9% was the rate of death for healthy people Mar 16, 2020 at 22:47
• @user8473907, but that table doesn't distinguish between healthy 10-year-olds and healthy 90-year-olds. To figure out if healthy young individuals are dying, you need a two-dimensional table that shows both age and health status.
– Mark
Mar 16, 2020 at 22:49