This is how the Associated Press reports the German results of the European Parliament election:
German Chancellor Angela Merkel's conservatives were headed for a center-right majority and her center-left rivals for a historically heavy defeat Sunday in European Parliament elections, according to projections.
Bloomberg writes:
German Chancellor Angela Merkel’s Christian Democrats beat the Social Democrats in European Parliament elections yesterday with less than four months to go before a national vote, preliminary final results showed.
…
“It’s a very successful election for Merkel,” Jan Techau, an analyst at the Berlin-based German Council on Foreign Relations, said in an interview. “It’s a pretty strong signal that German voters prefer the center-right parties because people expect them to be more competent on the economy.”
Now compare those news reports with the facts.
This chart, snipped from the Süddeutsche Zeitung, shows the percentage point changes from the last European Parliament election to yesterday's one.

Merkel's CDU/CSU lost 6.6 percentage points or 23% of its last time voters while the Social Democrats' SPD lost 0.7pp. The Greens gained 0.2. The big winner was the slightly libertarian FDP with a 4.9 win. The left gained 1.4 and all others gained 0.9.
How can Merkel's major loss of 6.6 percentage points be interpreted as a "very successful election" while the potential left-of-center-coalition of SPD/Greens/Linke which gained 0.9 in total is seen as having had a "historically heavy defeat"?