If latex can’t fill a page (perhaps because the next object is a figure or table that doesn’t fit, or because the next object is a heading that latex doesn’t want to put at the foot of a page) then by default it will spread the vertical white space on the page so that the „height“ of the page is the default height. If you want all the extra white space to appear at the bottom of such pages, add \raggedbottom before your \begin{document} line.
Quelle: Cambridge University Engineering Department – Squeezing Space in LaTeX
Wie lange habe ich mich darüber aufgeregt? Endlich ist die Lösung da …
