This is the story of how Spec Richardson and Tal Smith conspired to turn one of the organization's most beloved sluggers into nothing over the course of 5 seasons.
Generation 0
The Toy Cannon was selected by Houston from Cincinnati in what was then the precursor to the Rule Five draft in November of 1962. After a couple years of part time use he took over the starting center field role in 1965 and blossomed, hitting .275/.371/.470 with 22 home runs and 43 steals. He was an All-Star in 1967, a year in which he hit 37 homers with 107 rbi despite leading the league with 137 strikeouts. 1969 was another exceptional year for Jimmy as he lead the league in walks with 148 while hitting 33 homers, scoring 113 runs, and putting up a 166 OPS+. All told, he accumulated 41.4 WAR in his 11 years with Houston. Following the 1973 season, Wynn was traded to the Dodgers for David Culpepper and Claude Osteen. Wynn was an All-Star both years he was in LA but declined quickly after that and was done following the 1977 season. His number was retired by the Astros in 2005 and he currently works with the club on community outreach.
Generation 1
David Culpepper was a 22 year old minor league reliever when he moved to the Houston organization. He never made the major leagues, topping out at AAA where he put up a 4.62 ERA with more walks than strikeouts in 41 appearances over parts of three seasons. His playing career ended in 1976.
Claude Osteen was a 34 year old, three time All-Star, including the 1973 season, prior to joining the Astros. After going 9-9 with a 3.71 ERA (93 ERA+) and accumulating .5 WAR in 23 games for Houston, the Astros traded him in August of 1974 to the Cardinals for Ron Selak and a PTBNL. The PTBNL ended up being Dan Larson when the trade was completed in October of that year. After finishing the season with St Louis, he was picked up as a FA by the White Sox for what would be the final season of his career in 1975. Over his 18 year career he won 196 games and was part of the World Champion 1965 Dodgers team. Following his career he had a long and successful career as pitching coach, including a 7 year stint with Philadelphia that saw his pitchers win three Cy Young Awards.
Generation 2
Ron Selak arrived in Houston as a 19 year old promising AA starting pitcher but never fulfilled his potential. After 8 starts for the Astros AA squad to finish 1974 and begin 1975, Selak was promoted to AAA but he struggled to a 4.39 ERA in AAA over 443 innings for Houston before returning to the Cardinals organization for just 4 AAA starts in 1978 before his career ended.
Dan Larson was a 20 year old AA starter at the time of his trade to Houston. Despite pedestrian numbers in the minors, he made his major league debut in 1976 and pitched admirably for a 21 year old rookie, putting up a 3.02 ERA (106 ERA+) in 92.1 innings. He struggled the following year as he pitched to a 5.81 ERA while bouncing between starting and relieving, then spent nearly all of 1978 back in the minors. He totaled (-1.2) WAR his two seasons with the Astros before being traded to Philadelphia towards the end of the 1978 season for Dan Warthen. Larson spent parts of the next five seasons as the definition of replacement level then pitched to more years in the minors before his career ended.
Generation 3
Dan Warthen's story is remarkably similar to Dan Larson's. After a promising debut with Montreal in 1975, Warthen's performance dropped considerably and, at the time of his trade to Houston, he was back in the minors. He would finish the 1978 season in the majors with the Astros, pitching to a 4.22 ERA in five games. He was released in March of 1979. After signing with Pittsburgh, Dan finished his career with four more minor league seasons. After his playing career, Warthen went on to serve as pitching coach and bullpen coach for a number of teams and currently serves in that capacity for the Mets.
After writing all that, seeing how quickly the Toy Cannon declined, it's probably not fair to pillory the Astros' front office of the late 70s. Though it would have been nice to get those two All-Star years from Wynn.