Grit is important

Grit is most important criteria if you want to be successful trader. 

If you have grit then you will overcome many psychological obstacles. If you study most successful traders it took them 10 years or so to become consistent. Most people do not persist that long and give up because they blow up or do not have grit. early failure leads to fast exit. 

After trading 14 years profitably and talking to many other traders the consistent theme is ability to persist in initial years after many setbacks. Some blow up multiple times before finding their unique edge. The edge they find may not be big but the process of trial and error and persistence leads to their unique personality that can not be easily replicated.

Grit and self efficacy beliefs are biggest determinant of success in this field.

Most edges are small but how you play around with them is what matters. Take a small edge and marry it with well thought out process flow and good risk management and you will develop a larger edge.

but if you have grit it will work , absent that this is difficult game for many.