Biggest Improvements and Declines between Tournaments

[Satchmo Distel]

Going by two-year cycles:

Decline:

Netherlands: decent in 1980 Euros, DNQ 1982

Italy: winners 1982, DNQ 1984. Third place 1990, DNQ 1992. RU 1994, group stage 1996.

Improvement:

Sweden: Dire in 1990, very decent 1992, excellent 1994.

Czechia, Denmark and Greece all won a Euros after a DNQ World Cup. Proof maybe that you don't need four years to build a top side.

Italy won in 1968 after a dire 1966

England: woeful 2016, SF 2018

[jwdd27]

England in the decline bracket: SF 90, group stage 92, dnq 94

[Walt Flanagans Dog]

France: winners 1998, 2000, tanked badly in 2002

[Walt Flanagans Dog]

And similarly Spain, winners 2010, 2012, tanked in 2014.

[blameless]

Netherlands: 3rd at Brazil 2014, fell off a cliff and missed both Euro 16 and Russia 2018. Back at Euro 2020.

[Discordant Resonance]

Ireland went from the last 16 of USA 94 to drawing with Liechtenstein in failing to qualify for Euro 96.

[Simon G]

Improvement:

Sweden: Dire in 1990, very decent 1992, excellent 1994.

Sweden then went into decline immediately after by not qualifying for Euro 96 or the 98 World Cup.

Also:
Croatia: 98 - 3rd, 2000 - DNQ
Wales: 2016 - SF, 2018 - DNQ

[G-Man]

Decline:

Germany: Six successive World Cup and Euro semi-finals between 2006 and 2016. Then the disaster of 2018, 0-6 in Spain, 1-2 at home to N. Macedonia, and third favourites in their group of four.

[Satchmo Distel]

Germany also went from winning Euro 96 to being dire in Euro 2000. England SF to dire in the same timeframe.