Other have said this before but it bears to be repeated again lest the new round of ending hatred overshadows it: The ending, while extremely problematic, irrational, and ill executed, was not wholly unexpected and is only ~1% of the game. It is the other 99% of the game that the REAL problems lie. In fact, arguably the current backlash at the ending can be considered a projected scapegoat for the previous parts that failed to do their mission.
Before ME3 started, there were several very clear and pressing goals that not only should be but must be fullfilled to ensure plausible, satisfactory adherence to the plot and expectations laid out by ME1 and ME2:
1. Deeper, more intimate character interactions with squadmates from ME1, possibly ME2
2. Tie up any loose threads with recurring NPCs. Former ME2/ME1 squadmates play prominent, respectable roles
3. Have previous plot integral choices made in ME1/ME2 impact story in fight against Reapers in tangible ways
4. Have decisions made within ME3 impact its story in tangible ways.
5. Be able to manage and prosecute war against Reapers in significant ways
6. Have background, mythology, and teleology of the Reapers and universe at large explained substantially if not completely.
From the responses everywhere it seems nearly everyone faults the final ending for not fullfilling.....the entire list of priorities listed above. Which is neither reasonable nor possible, as the mere 5-6 minutes will demonstrate. To do so you must have a good 15-20 hours minimum PRIOR to the ending for that purpose. Now, the questions should be, did the previous 99% of the game do the job it's supposed to do ? And the answer is no.
Autodialogue nearly ruined #1, with judiciously used cutscenes barely salvaging your relationships with your squadmates. #2 virtually converted living, breathing characters into 2D statistics for your war assets, and then junked them forever. NPCs on the other hand, received a better send off. For #3, well, we have gone over that part endless times. #4, we spent so much time and effort gathering our fleet, and what we did we receive? A good cutscene 1 hour before the end, and that's it. We only brought it to only one place, have no idea how it fared in the start, middle, and end as Shepard was on Earth. We have no idea just how positive or negative it impacted Shepard's time on Earth, despite it arguably being THE main goal in ME3. #5 is perhaps the most egregious offender. Half of the missions (more if side missions included) involve fighting Cerberus, who with no explanation became your foremost enemy and with no power to placate or ally with them despite doing so in ME2 ( and people thought the Crucible was a bad McGuffin!) The whole ordeal resembled an empty goose chase with no discernable benefit for the war effort save to merely get ride of a bad distractor. What we saw of the Reapers before the end were mere shadows, figments, fragments. There was very little dread, tension, or epicness associated with them. Where were the awe inspiring battlefields? The overarching space battles? The sense of scale? Only a smidgen in the end, it seems. As a sidenote, how are we expected to feel and mourn for the fall of Palaven and Thessia, when we barely knew them in begin with? And for #6, well, we got none of it, nada, zilch, during the course of the game, until a 2-3 minute sudden, unclear info dump at the end, then credits roll.
To reiterate the point, the ending should not the object of wrath here. It's the other 99% before it that is the chief offenders for creating so horrible a road, that the ending, with the way it is, was all but inevitable.
