It is convenient to blame the weather of course.
This part of the lecture series was written by Dr. Russell F. Weigley, Professor of History, Temple University.
This part of the lecture can be read in whole here:
http://www.k-state.edu/history/specialevents/Eisenhowerlecture/eisenhower4.htm
Operation MARKET"‘GARDEN (17"‘25"‘ September 1944), the combined airborne and ground effort to capture a bridgehead across the Neder Rijn at Arnhem in the Netherlands that would outflank German's Westwall defenses, is the most dramatic evidence of the extent to which Eisenhower gave Montgomery the opportunity to effect his favored strategy. For MARKET"‘GARDEN Montgomery received a heavily disproportionate share of Allied logistical resources, particularly fuel, and of course practically Allied air transport capacity. He received the theater's only major troop reserve, the First Allied Airborne Army The operation failed not because it was accorded inadequate resources or because for that or any other reason it was doomed from the start "‘ it was a sound strategic conception, for which Montgomery merits credit as its principal author "‘
but because Montgomery, his 21 Army Group headquarters, and his immediately subordinate commands failed to obtain adequate intelligence of enemy dispositions and supply adequate control of tactical execution.
To the extent that Montgomery's ambitions were in fact curtailed by logistical shortages, the main cause was not any lack of support from Eisenhower but the unavailability of the port capacity of Antwerp (Antwerpen), the largest seaport of northwestern Europe. Montgomery's troops had captured this port on 3 September, but the port was not actually opened to regular shipping until 26 November. The reason was that having captured it, Montgomery failed to move quickly to clear the islands and waterways between Antwerp and the North Sea. Eisenhower pressed him hard to do so from the outset, but it was not until the Supreme Commander yielded his preference for granting his subordinates wide discretionary authority and virtually ordered Montgomery to give first priority to opening Antwerp that the field"‘marshal at length acted to remove the logistical noose that through his neglect of Antwerp he had tied around his own neck.Altogether, it must be repeated, Eisenhower accorded Montgomery every opportunity short of imperiling the rest of the Allied armies to realize the ambition of a primarily British narrow thrust into Germany. He did so for the excellent reason that in spite of the risks it entailed, Montgomery's design offered the best chance for winning the war before the end of the autumn of 1944.
The narrow thrust failed partly because of Montgomery's own mistakes, in the faulty tactical conduct of MARKET"‘GARDEN and in delaying clearance of Antwerp, and to a greater extent because Allied resources were simply not sufficient to support the design.
Why use wiki when you have far better source? How is the weather in Tibet btw?