The Black Eagles lost 2-0 against Galatasaray at the Türk Telekom Arena ending any chance of qualifying for the Champions League next season.
“Sure there is an element of being unlucky but the fact of the matter is we lack that touch of quality and experience our rivals have,” Bilic told Lig Tv after the game.
“Look at Wesley Sneijder, he has scored at least 30 goals in big games like that for Real Madrid and Inter, that is the difference between us, it is a huge advantage for Galatasaray and we need players like that.”
Sneijder scored the winning goal against Beşiktaş and now has a total of 14 goals and six assists this season.
The Galatasaray star has won the league title in every country he has played in including Spain, Italy, Netherlands and Turkey.
The 30-year-old playmaker also won the Champions League and World Club Cup during his time at Inter.
The Netherlands international captain will lift the Süper Lig title for the second time since joining Galatasaray in 2013 should the Lions win the championship this season.
Bilic will leave Beşiktaş at the end of the season and is expected to take over at West Ham.