[Shaun]

I was curious to see if it really is as simple as "if it won't make our charts, it's a flop and we'll end up bottom" and...well...

2001: "No Dream Impossible" by Lindsay - finished 15th in Eurovision - UK singles chart position: 32
2002: "Come Back" by Jessica Garlick - finished 3rd in Eurovision - UK singles chart position: 13
2003: "Cry Baby" by Jemini - first ever nul points for us - UK singles chart position: 15 (worth noting it was... beyond awful performed live, though)
2004: "Hold Onto Our Love" by James Fox - finished 16th in Eurovision - UK singles chart position: 13
2005: "Touch My Fire" by Javine - finished 22nd in Eurovision - UK singles chart position: 18
2006: "Teenage Life" by Daz Sampson - finished 19th in Eurovision - UK singles chart position: 8 - another odd one out here, probably because this was so chavvy and UK-orientated that it was never going to succeed anywhere else
2007: "Flying the Flag (For You)" by Scooch - finished 22nd in Eurovision - UK singles chart position: #5 - the most "novelty" song we've ever sent, and had the unfortunate position of following Verka Serduchka, so I think Europe were all camped-out.
2008: "Even If" by Andy Abraham - finished last in Eurovision - UK singles chart position: 67
2009: "It's My Time" by Jade Ewen - finished 5th in Eurovision - UK Singles Chart position: 27
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2010: "That Sounds Good To Me" by Josh Dubovie - finished last in Eurovision - UK singles chart position: 179
2011: "I Can" by Blue - finished 11th in Eurovision - UK Singles Chart position: 16
2012: "Love Will Set You Free" by Engelbert Humperdinck - finished 25th (1 above last) in Eurovision - UK singles chart position: 60
2013: "Believe In Me" by Bonnie Tyler - finished 19th in Eurovision - UK singles chart position: 93
2014: "Children of the Universe" by Molly - finished 17th in Eurovision - UK singles chart position: 27* - the odd one out in this list... we liked it enough to chart, but IIRC she had a bit of a disaster during the Jury performance and was out of tune?
2015: "Still in Love With You" by Electro Velvet still disgusted we even sent this - finished 24th in Eurovision - UK singles chart position: 114
2016: "You're Not Alone" by Joe and Jake - finished 24th in Eurovision - UK singles chart position: 81
2017: "Never Give Up On You" by Lucie Jones - finished 15th in Eurovision - UK singles chart position: 73
2018: "Storm" by SuRie - finished 24th in Eurovision - UK singles chart position: 50
2019: "Bigger Than Us" by Michael Rice - finished last in Eurovision - UK singles chart position: did not chart
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2021: "Embers" by James Newman - finished last in Eurovision - UK singles chart position: 47 (and most of that is sympathy downloads)

So from this we can surmise... if it doesn't make our own charts, there's a good chance it's going to finish last in the competition. The 2000s saw a lot of cases of songs making our charts but flopping at Eurovision, and that's inevitably down to two factors:

1) It was far easier to chart in the 2000s than it is today. Physical sales were beginning to die, and downloads and airplay were the only way to make the charts. Streaming didn't exist for Daz Sampson, Scooch or Javine, so it only really took a couple of thousand downloads to make it as high as they did in our charts.
2) Our selection processes were usually aired on BBC One, gathering a huge amount of promotion for the singles involved. Terry Wogan and - I think? - Tess Daly would host it and it'd get pretty good viewing figures. Nowadays even if we have a voting process, it's shelved away over on BBC Four and gets around 500,000 viewers, if that.

Compare all of these occasions to our 90s successes... these songs finished top 5 in Eurovision.

1992: Michael Ball (2nd) - #20 in our charts
1993: Sonia (2nd) - #15 in our charts
1997: Katrina and the Waves (winner) - #3 in our charts
1998: Imaani (2nd) - #15 in our charts

Going back further than that is probably not worthwhile since finishing 2nd in Eurovision when there was, like, 12 countries taking part isn't that impressive