The Revolutions of 1848 led to:
Sure, not everything the revolutionaries wanted they got, and in many places the changes were not achieved, or reversed in the immediate term. It would take the subsequent decades for the seeds of Nationalistic, Liberal, and Socialist forces planted during 1848 to grow by the late 19th century.
By comparison, the French Revolution of 1789 is considered to be of monumental importance, a defining point in modern civilization, while the 1848 revolutions are considered a fad, a failure. Why so? If anything, the immediate achievements of the French Revolution of 1789 (republicanism, universal male suffrage, Rights of Man and specifically rights of the poor Sans-Culottes) were soundly reversed by the mid-to-late 1790s (and not before a disastrous and bloody civil war and reign of Terror), without ever spreading out of the country, and arguably the longest-lasting achievement was the rise of Napoleon and his own achievements such as the Napoleonic Code. Whereas the liberal and nationalistic ideas espoused in the Revolutions of 1848 were achieved on a much closer timescale after they happened, if still not immediate, and transformed Europe as a whole.
So by their long-lasting legacy, one could argue the Revolutions of 1848 were of bigger impact on Western civilization than the French Revolution of 1789. Is there a reason, therefore, many consider the Revolutions of 1848 a failure?
The revolutions of 1848 can be considered a failure because of how they ended up. Let's look at them one by one:
France - France might be the most successful and changed one, with the overthrow of the July Monarchy and the establishment of a republic. Except that said Republic would be gone within 4 years, and had just elected Napoleon's nephew (Napoleon III) as President. Additionally, in the June Days, the second french republic had turned its back on much of the Parisian popular support (think the workers, socialists, etc - those who wanted the revolution to solve social problems, along with the political ones).
Germany - the Frankfurt Parliament (which had tried to unify Germany, a major goal of the liberals there) was forcefully dissolved, after the Prussian King had refused the 'crown from the gutter'.
Austria - the revolutionaries in Vienna were put down by the army, and much of the reforms rolled back - and, of course, they did not join in a greater germany.
Hungary - the revolutionaries in Hungary were put down militarily, and brought back under central Austrian rule.
Italy - the first war of Italian Independence was crushed, Lombardy and Venetia were retaken by the Austrians, the Roman Republic was returned to the Pope, etc.
Prussia - instead of a constitution drafted by the Prussian National Assembly, the King proclaimed one that was more to his liking. Then the conservatives won big in the elections there.
Poland - obviously, total failure and crushing of the revolution there.
On the whole, by 1849 all of the non-French revolutions of 1848 had been crushed. Though some reforms had been made, in none of these territories were the goals of the revolution met - and even in France, the fact that a Bonaparte was in power, and the repression of the June Days was a sign of the failure of the revolution, if you were inclined to look at it that way.
In contrast, the French Revolution of 1789 was one of the most momentous events in world history. Even if we look at it cynically, with it ending either with Napoleon coming to power (in 1799) or the restoration (1814), there were still massive changes kicked off by it. Internally in France, much of the reforms were kept - France under and after Napoleon was massively different from the Ancien Regime. Culturally, it had changed massively too - prior to 1789, the radical edge of politics was those who wanted a constitutional monarchy. Almost no one would have dreamed of establishing a republic.
But after the revolution, it was almost like a specter looming over Europe. Everyone would point at it - for inspiration, to demonize, to fear, to hope for.
The ideas of 1848 are inexorably linked to those of the French Revolution of 1789. The Revolution and the wars that followed it absolutely molded Europe and shook the existing order up. In contrast, though the Revolutions of 1848 did have some effect - they were not a complete 'game-changer', and were stamped out in under two years.