Take the plug out, hold it against the cooling fins with a rubber glove, pull the engine over? is there a spark?
pull the thing a few more times.sniff the plu hole, can you smell unburnt petrol?
put you thumb over the plug hole, pull it again, is the cylinder compressing ?
no to any of those is the primary cause. and it has to be one of them. The only thing theres no quick check for is timing, but small engines like that cant really slip there timing.