There were many reasons for Stresemann's success, as I will now explain.
Germany's industry levels, thanks to increased foreign investment, were back to those of 1913. Germany was an industry-led country, so getting industry back to a profitable level caused the whole country to run smoother. This was a success as it showed that Germany was rebuilding itself and restoring itself to its former glory.
As a result of this, and with increasing presence in the world trade, German exports rose by 40% between 1924 and 1929. This showed that the rest of the world were no longer feeling threatened by Germany, and accepted their desire to move forward and rebuild.
However, it can't all be seen as a success. Although there was economic growth, it was extremely uneven. There were more imports than exports, meaning that Germany was still losing money. This shows a failure on Stresemann's behalf as he should of focused on exports rather than imports, as this would of benefitted the country overall.
Also, unemployment rates never fell below 1.3 million. So, although industry appeared to be booming, there were many people still living in poverty-struck conditions.