A good Wordle starting word maximizes the information you get from your first guess. The ideal word has:

1. All unique letters — no repeats, so each tile gives you new information.
2. High-frequency letters — letters that appear in the most words, so you're likely to get greens and yellows.
3. Familiarity — a word you can remember and type quickly, especially in Speed Streak mode.

These rankings are computed from the actual 1,942 daily-tier words in the Japanese word list — not generic English advice. Letter frequencies vary significantly between languages, so starting words that work for English may not be optimal for Japanese.