are there any doping incidents?
Yes -  Russia has had 44 Olympic medals stripped for doping violations – the most of any country
Olympic Games
Doping in Russian sports has a systemic nature. Russia has had 44 Olympic medals stripped for doping violations – the most of any country, more than three times the number of the runner-up, and more than a quarter of the global total. From 2011 to 2015, more than a thousand Russian competitors in various sports, including summer, winter, and Paralympic sports, benefited from a cover-up. Russia was partially banned from the 2016 Summer Olympics and was banned from the 2018 Winter Olympics (while being allowed to participate as the Olympic Athletes from Russia) due to the state-sponsored doping programme.

In December 2019, Russia was banned for four years from all major sporting events for systematic doping and lying to WADA. The ban was issued by WADA on 9 December 2019, and the Russian anti-doping agency RUSADA had 21 days to make an appeal to the Court of Arbitration for Sport (CAS). The ban means that Russian athletes will not be allowed to compete under the Olympic flag. Russia is 
why olympic games are regarded as global events Thousands of athletes from around the world participate in the competitions from more than 200 nations. when did these games start? 1896 how does it benefit host cities? It increases the host country's exports, as the host or candidate country sends a signal about trade openness when bidding to host the Games. It has a strong positive effect on the philanthropic contributions of corporations headquartered in the host city, which seems to benefit the local nonprofit sector. have there been any incidents of boycott? Yes - There were three boycotts of the 1956 Melbourne Olympics: the Netherlands, Spain, and Switzerland refused to attend because of the repression of the Hungarian uprising by the Soviet Union.
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Olympic Games [SEP] Russian doping scandal
Doping in Russian sports has a systemic nature. Russia has had 44 Olympic medals stripped for doping violations – the most of any country, more than three times the number of the runner-up, and more than a quarter of the global total. From 2011 to 2015, more than a thousand Russian competitors in various sports, including summer, winter, and Paralympic sports, benefited from a cover-up. Russia was partially banned from the 2016 Summer Olympics and was banned from the 2018 Winter Olympics (while being allowed to participate as the Olympic Athletes from Russia) due to the state-sponsored doping programme. In December 2019, Russia was banned for four years from all major sporting events for systematic doping and lying to WADA.