When thinking about "why VCs...", keep in mind they have to invest in something. If they don't invest, they lose (lose LPs, lose the fund). So simple answer is

When thinking about "why VCs...", keep in mind they have to invest in something. If they don't invest, they lose (lose LPs, lose the fund). So simple answer is - they invested in this company because it was the least worse idea pitched to them over a certain period.