Could someone explain the different ways that a team having an awful year can benefit from their record in the off season?

I see that in 2002, the Cubs finished with a 67-95 record. The following year, they went 88-74 and we Cubs fans had an exciting year.

What does MLB (Major League Baseball) offer poorly performing teams to make them more competitive the following year?

2002 record 67-95, Finished 5th in NL Central Division
http://www.baseball-reference.com/teams/...

2003 record 88-74, Finished 1st in NL Central Division
http://www.baseball-reference.com/teams/...

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2006 record 66-96, Finished 6th in NL Central Division
http://www.baseball-reference.com/teams/...

2007 record ??-??, Finished ?th in NL Central Division