"Klotzen, nicht Kleckern!"
(Boot 'em, don't spatter 'em)
Guderian's favorite quotation. Adolf Hitler was so impressed by it that he used it often himself.

"Der Motor des Panzers ist ebenso seine Waffie wie die Kanone."
(The engine of the Panzer is a weapon just as the main-gun)
Too many of us treat a tank as a pillbox, ignoring its inherent mobility.

"Man schlagt jemanden mit der Faust und nicht mit gespreizten Fingern! "
(You must hit somebody with your fist, and not with your fingers spread.)
Guderian wanted his panzers concentrated into one fist aimed at what would hurt the enemy most. He opposed the distribution of his panzers in bits and pieces among the infantry for support.

"Der Kampf gegen die eigenen Oberen macht manchmal mehr Arbeit als gegen die Franzosen! "
(It is sometimes tougher to fight my superiors than the French)
Said when he got orders to stop and wait for the following infantry and tried to persuade his superiors that this would mean throwing away the victory.

"Es Gibt keine verzweifelten Lagen, es gibt nur verzweifelte Menschen!"
(There are no desperate situations, there are only desperate people)

"Fahrkarte bis zur Endstation."
(Ticket to the last station)
Shouting to his Panzer troops when they were roaring past him, meaning that they should go as far as they could, which they did.

"Between 8 & 17 February, the 9th Royal Tank Regiment & the 147th Regiment fought in the Reichswald and suffered 85 lank casualties. Of these, 17 were attributable to enemy action, 13 to turret failure, 3 to clutch failure, 20 to unspecified mechanical breakdown, and 32 to becoming hopelessly bogged down."

--J Ellis The Sharp End (p. 122)