Last team undefeated by season

I started to compile this, looking to see if there was a team which ended a teams winning streak to the season more that others.  What had me surprised the low amount of occasions where the last team to be defeated in a season ended up winning the flag in the end.  The premier of the season is marked ^ and the table excludes occasions where the two or three remaining undefeated teams lost in the same round:

2022 4-0 Glenelg 9.12 Port 10.9 (3 pts)
2021 17-0 Glenelg 5.8 Port 11.8 (36 pts)
2020 3-0 North 7.12 Eagles^ 10.8 (14 pts)
2019 5-0 Norwood 9.14 Adelaide 12.14 (18 pts)
2018 3-0-1 Eagles 13.4 North^ 14.7 (9 pts)
2017 6-0 Eagles 5.6 Norwood 9.13 (27 pts)
2016 6-0 South 7.4 Sturt^ 14.10 (48 pts)
2014 4-0 South 11.9 Eagles 13.7 (10 pts)
2013 4-0 West 6.5 Norwood^ 9.13 (26 pts)
2012 8-0 Norwood^ 10.11 North 11.6 (1 pt)
2011 3-0 West 9.9 Port 13.12 (27 pts)
2009 7-0 Central^ 11.9 Eagles 14.6 (15 pts)
2008 4-0 Sturt 13.12 Glenelg 15.14 (14 pts)
2007 8-0 Central^ 15.12 Sturt 17.7 (7 pts)
2006 5-0 Port 14.7 North 17.13 (24 pts)
2005 4-0 Eagles 13.11 South 20.8 (39 pts)
2004 3-0 North 10.8 Eagles 16.16 (44 pts)!
2002 6-0 Central 17.9 Norwood 20.4 (13 pts)
2001 6-0 Norwood 13.8 Eagles 16.9 (19 pts)
2000 4-0 Port 13.11 Sturt 19.14 (39 pts)~
1999 6-0 Port^ 9.16 West 11.10 (6 pts)
1997 10-0 Norwood^ 9.6 North 9.10 (4 pts)
1996 2-0 Glenelg 12.5 Eagles 14.18 (25 pts)
1995 4-0 Central 12.11 Port^ 23.13 (68 pts)
1994 7-0 Eagles 14.8 West 18.14 (30 pts)
1993 7-0 Port 13.14 Central 16.12 (16 pts)
1992 3-0 Norwood 11.21 South 16.20 (29 pts)
1991 5-0 Eagles 7.7 North^ 28.12 (131 pts)
1990 5-0 Glenelg 13.7 Norwood 16.8 (19 pts)
1989 11-0 North 8.12 Port^ 21.18 (84 pts)
1988 3-0 Glenelg 14.14 Sturt 16.13 (11 pts)
1987 3-0 Central 10.11 Torrens 16.10 (35 pts)
1986 3-0 Port 13.12 Norwood 21.13 (49 pts)
1985 11-0 North 12.16 Norwood 19.10 (36 pts)
1984 7-0 Port 8.16 Central 14.12 (32 pts)
1983 4-0 West^ 14.16 Norwood 16.6 (2 pts)
1982 3-0 North 10.9 South 16.11 (38 pts)
1981 10-0 Glenelg 9.14 Port^ 13.11 (21 pts)
1979 3-0-1 Torrens 9.7 South 14.16 (39 pts)
1978 5-0 Sturt 9.14 West 13.12 (22 pts)
1977 3-0 South 11.15 Glenelg 22.16 (67 pts)
1976 5-0 Glenelg 17.14 Port 18.18 (10 pts)
1975 9-0 Glenelg 19.13 Norwood^ 20.24 (17 pts)
1974 7-0 Sturt^ 13.17 South 16.8 (9 pts)
1973 6-0 Glenelg^ 8.22 North 14.13 (27 pts)
1972 6-0 Central 13.8 Port 16.24 (34 pts)
1971 6-0 Norwood 10.11 Sturt 17.18 (49 pts)
1970 17-0 Sturt^ 12.7 Port 12.13 (6 pts)
1969 11-0 Glenelg 8.15 Torrens 10.11 (8 pts)
1967 4-0 Glenelg 8.10 Port 9.11 (7 pts)
1966 3-0 South 10.10 Sturt^ 12.11 (13 pts)
1965 6-0 South 9.14 North 11.14 (12 pts)
1964 4-0-1 Norwood 5.7 South^ 12.12 (47 pts)
1963 5-0 North 9.11 Norwood 21.15 (76 pts)
1962 6-0-1 Norwood 8.11 West 21.19 (86 pts)
1961 5-0 Torrens 10.13 Port 14.15 (26 pts)
1959 4-0 West 7.12 Torrens 10.7 (15 pts)
1958 4-0 North 8.10 Port^ 14.14 (40 pts)
1957 8-0-1 Port^ 13.8 Norwood 12.24 (8 pts)
1956 13-0 Port^ 10.11 South 13.5 (12 pts)
1955 5-0 Sturt 10.14 Norwood 13.16 (20 pts)
1954 9-0 Port^ 6.14 Norwood 7.14 (6 pts)
1953 4-0 Glenelg 15.10 Norwood 15.22 (12 pts)
1952 4-0 Port 6.4 West 5.13 (3 pts)
1951 8-0 Port^ 4.14 Torrens 7.8 (12 pts)
1950 8-0 Norwood^ 12.7 West 12.21 (14 pts)
1949 5-0 Norwood 10.10 Port 19.13 (57 pts)
1948 3-0 Torrens 14.8 West 18.14 (30 pts)
1946 3-0 Port 13.9 West 13.14 (5 pts)
1945 12-0 Port 10.7 Sturt 19.20 (67 pts)#
1945 3-0 West 7.15 Norwood 8.16 (7 pts)
1941 7-0 Sturt 15.9 Port 16.16 (13 pts)
1940 6-0 Port 15.13 Torrens 15.15 (2 pts)
1939 6-0 Norwood 14.15 Torrens 18.18 (27 pts)
1938 5-0 Norwood 12.11 South^ 18.11 (36 pts)
1937 3-0 Norwood 8.15 Port^ 9.14 (5 pts)
1936 10-0 Port^ 14.17 Glenelg 16.10 (5 pts)
1935 4-0 Norwood 10.13 Torrens 14.16 (27 pts)
1934 3-0 Torrens 13.9 West 15.16 (19 pts)
1933 8-0 Sturt 10.10 Torrens^ 10.15 (5 pts)
1932 5-0 North 17.8 Port 16.15 (1 pt)
1931 5-0 Sturt 7.12 Port 8.13 (7 pts)
1930 3-0 Sturt 9.14 Norwood 14.13 (29 pts)
1929 5-0 Port 6.8 West 6.12 (4 pts)
1928 5-0 Port^ 7.23 West 25.7 (92 pts)
1927 7-0 Port 7.10 North 14.10 (42 pts)
1926 3-0 Torrens 7.18 North 10.6 (6 pts)
1925 4-0 Norwood^ 9.9 Torrens 12.16 (25 pts)
1924 3-0-1 Torrens^ 7.7 Sturt 8.11 (10 pts)
1923 11-0 Norwood^ 8.7 Port 18.8 (61 pts)
1922 5-0 Torrens 6.8 Norwood^ 18.8 (72 pts)
1921 4-0 Sturt 8.8 Norwood 12.13 (29 pts)
1920 3-0 Sturt 6.8 North^ 9.12 (22 pts)
1919 6-0 Sturt^ 8.13 Torrens 9.10 (3 pts)
1915 7-0-1 Port 4.11 West 7.10 (17 pts)
1913 3-0 Port^ 4.5 Sturt 9.13 (38 pts)
1912 13-0 Port 6.10 West 9.9 (17 pts)$
1911 10-0 West^ 5.8 Port 11.17 (45 pts)
1910 3-0 Port^ 7.9 Torrens 7.13 (4 pts)%
1909 4-0 West^ 4.11 North 5.10 (5 pts)
1908 4-0 Port 3.9 Norwood 4.15 (12 pts)
1907 4-0 Port 6.16 North 8.8 (4 pts)
1906 8-0 Port^ 7.9 Norwood 11.13 (28 pts)
1905 6-0-1 North^ 3.8 Port 7.13 (29 pts)
1904 8-0-1 Port 5.7 North 8.14 (25 pts)
1903 8-0 North 2.9 Port 3.7 (4 pts)
1902 4-0 South 2.4 North^ 4.8 (16 pts)
1901 5-0 Norwood^ 6.5 North 6.15 (10 pts)
1900 4-0 Torrens 2.4 North^ 5.10 (24 pts)
1899 4-0-1 Norwood 4.4 South^ 7.9 (23 pts)
1898 5-0 Norwood 5.3 South^ 11.9 (42 pts)

!North were 2nd on the ladder before the first defeat, owing to Central having a 3-1 record with a better percentage
~Sturt were last, and brought up their first win by defeating the only undefeated side
*In 1998, Port, West and Sturt were all 4-0 and had losses to North, Eagles and Central respectively in the next round.  This is the only occasion three teams were left undefeated, then in the next round, all lost.
#Technically Port were unbeaten to this point, however, they lost their opening round win due to playing an unregistered player.
The last to be defeated besides Port, is shown below that entry (West)
$Port went throughout the minor round undefeated; won the Semi Final, however lost the last two matches of the season to West, to hand West the flag
%Port were 2nd on the ladder before the first defeat, owing to Norwood having a 3-1 record with a better percentage

Only 27 out of the 103 seasons did the last team to be defeated, ended up winning the flag.  28 if you count Ports 1914 undefeated season.  Even the team which defeated the last remaining side only ended up with the pennant 18 times

15 out of the last 76 seasons did the team last to lose go on to win the title (19.74%)
9 out of the last 51 seasons (17.65%)

A couple of other things noticeable in that list - have a look at 1948 and 1994. The 1994 match took place one day shy of 46 years after 1948.
Norwood defeated Torrens 18.8 to 6.8 in 1922; the following season lost as the last unbeaten team to Port, 18.8 to 8.7