kläglich
pitiful
In a way that arouses pity or regret; pathetic or miserable.
Der verletzte Vogel bot einen kläglichen Anblick.
The injured bird made a pitiful sight.

pitiful
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pitiful
In a way that arouses pity or regret; pathetic or miserable.
Der verletzte Vogel bot einen kläglichen Anblick.
The injured bird made a pitiful sight.

The adjective 'kläglich' (pitiful) is derived from the verb 'klagen' (to complain/lament), which means 'jammern' (to whine) or 'sich beschweren' (to complain). Something that is 'kläglich' is therefore, in a sense, 'pitiful' or 'deplorable'.
Nach der Niederlage war die Stimmung in der Mannschaft kläglich.
After the defeat, the mood in the team was pitiful.
'kläglich' (miserably) is especially often used as an adverb in the fixed expression 'kläglich scheitern' (to fail miserably). This emphasizes that an attempt has failed completely and often in an embarrassing way.
Sein Plan, alle zu überraschen, ist kläglich gescheitert.
His plan to surprise everyone failed miserably.
In the meaning of 'erbärmlich' (pathetic), 'kläglich' (pitiful) often describes a state or sight. Typical nouns here are 'ein kläglicher Anblick' (a pitiful sight), 'ein kläglicher Zustand' (a pitiful state), or 'ein kläglicher Rest' (a pitiful remainder).
Vom großen Kuchen war nur noch ein kläglicher Rest übrig.
Only a pitiful remainder of the large cake was left.
When 'kläglich' (plaintive) describes a sound, it always refers to something quiet, sad, or miserable. It is often found in combinations such as 'eine klägliche Stimme' (a plaintive voice), 'ein klägliches Geräusch' (a plaintive sound), or 'ein klägliches Miauen' (a plaintive meow).
Das Kätzchen machte ein klägliches Geräusch, weil es Hunger hatte.
The kitten made a plaintive sound because it was hungry.
successful
'erfolgreich' and 'kläglich' form a clear contrast when it comes to success or failure. 'erfolgreich' describes a good result or an achieved goal. 'kläglich' describes a failure that is very obvious and often also embarrassing. 'kläglich' is stronger and more negative than simply 'not successful'. It is used, for example, for an attempt, a game, or an exam when almost nothing has succeeded.

Sein Versuch, den Computer selbst zu reparieren, scheiterte kläglich.
His attempt to repair the computer himself failed miserably.
Mit einem guten Plan haben die Eltern die Wohnungssuche erfolgreich beendet.
With a good plan, the parents successfully finished their apartment search.