How to keep pace in all season

I'm aasking some assistance for design setion.. if i've develop my car in 80-90% , it seems that next season car design fall to  20% and the result will be very poor.so how can i keep pace in every season ,i.e almost 70-80% in every season

I'm new here.  Why would car design fall back down to a lower level?

I assume that the design would fall to a lower level because, like in real life, every year there are a new set of guidelines and 'formulas' that the constructers must abide to, and therefore they have to redesign the cars every year.

Also, the system implemented here in the game prevents one particular team from dominating for extended periods of time.

Design comes with an exponential decline in improval, so the higher your percentage, the less you get per update. Also, you either focus on the current season or the next. As I said yesterday, it's about balance (ying yang included), unless you want a lightswitch career; on and off per season.