We look at three main factors: Number of wins, Number of Appearances, Population.
We want a country that wins almost as often as it appears, so we calculate the win/appearance ratio.
To reduce the amount of competition you may face in winning your national contest to qualify for Eurovision, we also want a country with a relatively small population. So, we calculate wins per appearance per 100 million people.
The microstate Monaco has appeared 24 times, won only once, and has a population of >40,000. Their win per appearance per 100 million people is 108.7. That's over 38 times higher than the average.
Generally, songs in major keys are considered more joyful (left side).
Songs in minor keys are considered more sad or emotional (right side).
The most successful minor keys (A, D, and E) and these are usually slower (60-140 bpm).
The most successful major keys are also the most successful overall: D and F.
Songs in major keys are faster or medium paced (80-180 bpm)
More seriously, part of why Eurovision is so interesting is that it is not immune to politics:
1. In 2014 Russia invaded Ukraine and annexed Crimea. This contributed to Jamala's "1944", sung in Crimean Tartar, winning the 2016 competition.
2. After winning in 2018, Israel hosted the 2019 competition. Some performers boycotted the event. They came in 23rd/26.
3. Amid Brexit, the UK saw back-to-back last-place performances. Receiving an almost unprecedented 0 votes in 2021.
4. In 2022, After Russia's full-scale invasion, Ukraine won the 2nd most points ever received in Eurovision history. Russia has been banned since 2021.