Recessions are very difficult to completely avoid; there is a natural business cycle that occurs. When time are good, businesses tend to think they'll last forever and over produce. At some point, an excess of inventory requires businesses to slow down. Add in all kinds of other shock producing effect from oil prices to market corrections, and it is very difficult to control.
For all the bandering about of how great the economy is or isn't, the president has limited control over the economy. Fiscal stimulus like govt spending and tax cuts have a small or insignificant overall effect on the economy. The greater effects are caused by money supply and interest rate manipulations, which the Fed does, not the President or congress. And the Fed has to balance a healthy economy against keeping inflation in check.
Arguably, the Fed has done a pretty good job, since Volcker was appointed in 1979. After the nasty rescession in 82, recessions in 92 and '01 were relatively mild, -- the '01 "recession" was arguably not a rescession at all, there were never 2 consecutive down quarters (the classic definition of a recission) and real GDP grew .7% overall that year.